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Sample records for synthetic acceleration method

  1. Diffusion-synthetic acceleration methods for discrete-ordinates problems

    International Nuclear Information System (INIS)

    Larsen, E.W.

    1984-01-01

    The diffusion-synthetic acceleration (DSA) method is an iterative procedure for obtaining numerical solutions of discrete-ordinates problems. The DSA method is operationally more complicated than the standard source-iteration (SI) method, but if encoded properly it converges much more rapidly, especially for problems with diffusion-like regions. In this article we describe the basic ideas behind the DSA method and give a (roughly chronological) review of its long development. We conclude with a discussion which covers additional topics, including some remaining open problems an the status of current efforts aimed at solving these problems

  2. A transport synthetic acceleration method for transport iterations

    International Nuclear Information System (INIS)

    Ramone, G.L.; Adams, M.L.

    1997-01-01

    A family of transport synthetic acceleration (TSA) methods for iteratively solving within group scattering problems is presented. A single iteration in these schemes consists of a transport sweep followed by a low-order calculation, which itself is a simplified transport problem. The method for isotropic-scattering problems in X-Y geometry is described. The Fourier analysis of a model problem for equations with no spatial discretization shows that a previously proposed TSA method is unstable in two dimensions but that the modifications make it stable and rapidly convergent. The same procedure for discretized transport equations, using the step characteristic and two bilinear discontinuous methods, shows that discretization enhances TSA performance. A conjugate gradient algorithm for the low-order problem is described, a crude quadrature set for the low-order problem is proposed, and the number of low-order iterations per high-order sweep is limited to a relatively small value. These features lead to simple and efficient improvements to the method. TSA is tested on a series of problems, and a set of parameters is proposed for which the method behaves especially well. TSA achieves a substantial reduction in computational cost over source iteration, regardless of discretization parameters or material properties, and this reduction increases with the difficulty of the problem

  3. Diffusion synthetic acceleration methods for the diamond-differenced discrete-ordinates equations

    International Nuclear Information System (INIS)

    Alcouffe, R.E.

    1976-01-01

    A class of acceleration schemes is investigated which resembles the conventional synthetic method in that they utilize the diffusion operator in the transport iteration schemes. The accelerated iteration involves alternate diffusion and transport solutions where coupling between the equations is achieved by using a correction term applied to either the diffusion coefficient, the removal cross section, or the source of the diffusion equation. The methods involving the modification of the diffusion coefficient and of the removal term yield nonlinear acceleration schemes and are used in k/sub eff/ calculations, while the source term modification approach is linear at least before discretization, and is used for inhomogeneous source problems. A careful analysis shows that there is a preferred differencing method which eliminates the previously observed instability of the conventional synthetic method. Use of this preferred difference scheme results in an acceleration method which is at the same time stable and efficient. This preferred difference approach renders the source correction scheme, which is linear in its continuous form, nonlinear in its differenced form. An additional feature of these approaches is that they may be used as schemes for obtaining improved diffusion solutions for approximately twice the cost of a diffusion calculation. Numerical experimentation on a wide range of problems in one and two dimensions indicates that improvement from a factor of two to ten over rebalance or Chebyshev acceleration is obtained. The improvement is most pronounced in problems with large regions of scattering material where the unaccelerated transport solutions converge very slowly

  4. New methods of acceleration

    International Nuclear Information System (INIS)

    Ivanov, I.N.; Sarantsev, V.P.

    1976-01-01

    The most perspective methods of the collective acceleration of particles are considered, namely, acceleration of ions in direct electron beams and electron rings. Several models of particle acceleration by means of electron beams are described. Experimental data on the acceleration of differently charged ions show that the ion energy increases with the charge. Time-of-flight measurements show that during acceleration the ion bunch is located behind the beam front. The injection of electrons into an electron-ring accelerator and the electron acceleration are considered in detail. The most dangerous effects are described, which restrict the number of particles captured in the electron-ring accelerator. Several mechanisms are considered for retaining the cross-sectional dimensions of the moving ring

  5. Transport synthetic acceleration with opposing reflecting boundary conditions

    International Nuclear Information System (INIS)

    Zika, M.R.; Adams, M.L.

    2000-01-01

    The transport synthetic acceleration (TSA) scheme is extended to problems with opposing reflecting boundary conditions. This synthetic method employs a simplified transport operator as its low-order approximation. A procedure is developed that allows the use of the conjugate gradient (CG) method to solve the resulting low-order system of equations. Several well-known transport iteration algorithms are cast in a linear algebraic form to show their equivalence to standard iterative techniques. Source iteration in the presence of opposing reflecting boundary conditions is shown to be equivalent to a (poorly) preconditioned stationary Richardson iteration, with the preconditioner defined by the method of iterating on the incident fluxes on the reflecting boundaries. The TSA method (and any synthetic method) amounts to a further preconditioning of the Richardson iteration. The presence of opposing reflecting boundary conditions requires special consideration when developing a procedure to realize the CG method for the proposed system of equations. The CG iteration may be applied only to symmetric positive definite matrices; this condition requires the algebraic elimination of the boundary angular corrections from the low-order equations. As a consequence of this elimination, evaluating the action of the resulting matrix on an arbitrary vector involves two transport sweeps and a transmission iteration. Results of applying the acceleration scheme to a simple test problem are presented

  6. Transport Synthetic Acceleration with Opposing Reflecting Boundary Conditions

    International Nuclear Information System (INIS)

    Zika, Michael R.; Adams, Marvin L.

    2000-01-01

    The transport synthetic acceleration (TSA) scheme is extended to problems with opposing reflecting boundary conditions. This synthetic method employs a simplified transport operator as its low-order approximation. A procedure is developed that allows the use of the conjugate gradient (CG) method to solve the resulting low-order system of equations.Several well-known transport iteration algorithms are cast in a linear algebraic form to show their equivalence to standard iterative techniques. Source iteration in the presence of opposing reflecting boundary conditions is shown to be equivalent to a (poorly) preconditioned stationary Richardson iteration, with the preconditioner defined by the method of iterating on the incident fluxes on the reflecting boundaries. The TSA method (and any synthetic method) amounts to a further preconditioning of the Richardson iteration.The presence of opposing reflecting boundary conditions requires special consideration when developing a procedure to realize the CG method for the proposed system of equations. The CG iteration may be applied only to symmetric positive definite matrices; this condition requires the algebraic elimination of the boundary angular corrections from the low-order equations. As a consequence of this elimination, evaluating the action of the resulting matrix on an arbitrary vector involves two transport sweeps and a transmission iteration. Results of applying the acceleration scheme to a simple test problem are presented

  7. Synthetic seismic acceleration time-histories and their acceptance criteria

    International Nuclear Information System (INIS)

    Xu Hong

    1996-01-01

    In seismic dynamic response analysis of structures and equipment, time-history analysis is now widely used. The 3-D seismic acceleration time-histories or 3-D seismic displacement time-histories are required in the 3-D seismic dynamic response analysis as the seismic excitation input data. Because of the lack of actual acceleration time-histories for the field where the structures or equipment are installed, the general practice is to use the synthetic seismic acceleration time-histories, which are derived from the design seismic response spectra of the field, as the seismic excitation input data. However, from one specified design response spectrum indefinite solutions of acceleration time-histories can be derived depending on the values of the input parameters. Not all the derived synthetic time-histories can be used as seismic excitation input data. Only those which meet the acceptance criteria can be used. The factors (input parameters), which will affect the time-history solution from a specified seismic response spectrum, and the acceptance criteria are discussed

  8. Methods for preparing synthetic freshwaters.

    Science.gov (United States)

    Smith, E J; Davison, W; Hamilton-Taylor, J

    2002-03-01

    Synthetic solutions that emulate the major ion compositions of natural waters are useful in experiments aimed at understanding biogeochemical processes. Standard recipes exist for preparing synthetic analogues of seawater, with its relatively constant composition, but, due to the diversity of freshwaters, a range of compositions and recipes is required. Generic protocols are developed for preparing synthetic freshwaters of any desired composition. The major problems encountered in preparing hard and soft waters include dissolving sparingly soluble calcium carbonate, ensuring that the ionic components of each concentrated stock solution cannot form an insoluble salt and dealing with the supersaturation of calcium carbonate in many hard waters. For acidic waters the poor solubility of aluminium salts requires attention. These problems are overcome by preparing concentrated stock solutions according to carefully designed reaction paths that were tested using a combination of experiment and equilibrium modeling. These stock solutions must then be added in a prescribed order to prepare a final solution that is brought into equilibrium with the atmosphere. The example calculations for preparing hard, soft and acidic freshwater surrogates with major ion compositions the same as published analyses, are presented in a generalized fashion that should allow preparation of any synthetic freshwater according to its known analysis.

  9. Transport Synthetic Acceleration for Long-Characteristics Assembly-Level Transport Problems

    International Nuclear Information System (INIS)

    Zika, Michael R.; Adams, Marvin L.

    2000-01-01

    We apply the transport synthetic acceleration (TSA) scheme to the long-characteristics spatial discretization for the two-dimensional assembly-level transport problem. This synthetic method employs a simplified transport operator as its low-order approximation. Thus, in the acceleration step, we take advantage of features of the long-characteristics discretization that make it particularly well suited to assembly-level transport problems. Our main contribution is to address difficulties unique to the long-characteristics discretization and produce a computationally efficient acceleration scheme.The combination of the long-characteristics discretization, opposing reflecting boundary conditions (which are present in assembly-level transport problems), and TSA presents several challenges. We devise methods for overcoming each of them in a computationally efficient way. Since the boundary angular data exist on different grids in the high- and low-order problems, we define restriction and prolongation operations specific to the method of long characteristics to map between the two grids. We implement the conjugate gradient (CG) method in the presence of opposing reflection boundary conditions to solve the TSA low-order equations. The CG iteration may be applied only to symmetric positive definite (SPD) matrices; we prove that the long-characteristics discretization yields an SPD matrix. We present results of our acceleration scheme on a simple test problem, a typical pressurized water reactor assembly, and a typical boiling water reactor assembly

  10. Transport synthetic acceleration for long-characteristics assembly-level transport problems

    International Nuclear Information System (INIS)

    Zika, M.R.; Adams, M.L.

    2000-01-01

    The authors apply the transport synthetic acceleration (TSA) scheme to the long-characteristics spatial discretization for the two-dimensional assembly-level transport problem. This synthetic method employs a simplified transport operator as its low-order approximation. Thus, in the acceleration step, the authors take advantage of features of the long-characteristics discretization that make it particularly well suited to assembly-level transport problems. The main contribution is to address difficulties unique to the long-characteristics discretization and produce a computationally efficient acceleration scheme. The combination of the long-characteristics discretization, opposing reflecting boundary conditions (which are present in assembly-level transport problems), and TSA presents several challenges. The authors devise methods for overcoming each of them in a computationally efficient way. Since the boundary angular data exist on different grids in the high- and low-order problems, they define restriction and prolongation operations specific to the method of long characteristics to map between the two grids. They implement the conjugate gradient (CG) method in the presence of opposing reflection boundary conditions to solve the TSA low-order equations. The CG iteration may be applied only to symmetric positive definite (SPD) matrices; they prove that the long-characteristics discretization yields an SPD matrix. They present results of the acceleration scheme on a simple test problem, a typical pressurized water reactor assembly, and a typical boiling water reactor assembly

  11. Transport synthetic acceleration scheme for multi-dimensional neutron transport problems

    International Nuclear Information System (INIS)

    Modak, R.S.; Vinod Kumar; Menon, S.V.G.; Gupta, Anurag

    2005-09-01

    The numerical solution of linear multi-energy-group neutron transport equation is required in several analyses in nuclear reactor physics and allied areas. Computer codes based on the discrete ordinates (Sn) method are commonly used for this purpose. These codes solve external source problem and K-eigenvalue problem. The overall solution technique involves solution of source problem in each energy group as intermediate procedures. Such a single-group source problem is solved by the so-called Source Iteration (SI) method. As is well-known, the SI-method converges very slowly for optically thick and highly scattering regions, leading to large CPU times. Over last three decades, many schemes have been tried to accelerate the SI; the most prominent being the Diffusion Synthetic Acceleration (DSA) scheme. The DSA scheme, however, often fails and is also rather difficult to implement. In view of this, in 1997, Ramone and others have developed a new acceleration scheme called Transport Synthetic Acceleration (TSA) which is much more robust and easy to implement. This scheme has been recently incorporated in 2-D and 3-D in-house codes at BARC. This report presents studies on the utility of TSA scheme for fairly general test problems involving many energy groups and anisotropic scattering. The scheme is found to be useful for problems in Cartesian as well as Cylindrical geometry. (author)

  12. The Source Equivalence Acceleration Method

    International Nuclear Information System (INIS)

    Everson, Matthew S.; Forget, Benoit

    2015-01-01

    Highlights: • We present a new acceleration method, the Source Equivalence Acceleration Method. • SEAM forms an equivalent coarse group problem for any spatial method. • Equivalence is also formed across different spatial methods and angular quadratures. • Testing is conducted using OpenMOC and performance is compared with CMFD. • Results show that SEAM is preferable for very expensive transport calculations. - Abstract: Fine-group whole-core reactor analysis remains one of the long sought goals of the reactor physics community. Such a detailed analysis is typically too computationally expensive to be realized on anything except the largest of supercomputers. Recondensation using the Discrete Generalized Multigroup (DGM) method, though, offers a relatively cheap alternative to solving the fine group transport problem. DGM, however, suffered from inconsistencies when applied to high-order spatial methods. While an exact spatial recondensation method was developed and provided full spatial consistency with the fine group problem, this approach substantially increased memory requirements for realistic problems. The method described in this paper, called the Source Equivalence Acceleration Method (SEAM), forms a coarse-group problem which preserves the fine-group problem even when using higher order spatial methods. SEAM allows recondensation to converge to the fine-group solution with minimal memory requirements and little additional overhead. This method also provides for consistency when using different spatial methods and angular quadratures between the coarse group and fine group problems. SEAM was implemented in OpenMOC, a 2D MOC code developed at MIT, and its performance tested against Coarse Mesh Finite Difference (CMFD) acceleration on the C5G7 benchmark problem and on a 361 group version of the problem. For extremely expensive transport calculations, SEAM was able to outperform CMFD, resulting in speed-ups of 20–45 relative to the normal power

  13. Synthetic Self-Healing Methods

    Energy Technology Data Exchange (ETDEWEB)

    Bello, Mollie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-06-02

    Given enough time, pressure, temperature fluctuation, and stress any material will fail. Currently, synthesized materials make up a large part of our everyday lives, and are used in a number of important applications such as; space travel, under water devices, precise instrumentation, transportation, and infrastructure. Structural failure of these material scan lead to expensive and dangerous consequences. In an attempt to prolong the life spans of specific materials and reduce efforts put into repairing them, biologically inspired, self-healing systems have been extensively investigated. The current review explores recent advances in three methods of synthesized self-healing: capsule based, vascular, and intrinsic. Ideally, self-healing materials require no human intervention to promote healing, are capable of surviving all the steps of polymer processing, and heal the same location repeatedly. Only the vascular method holds up to all of these idealities.

  14. Iterative acceleration methods for Monte Carlo and deterministic criticality calculations

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, T.J.

    1995-11-01

    If you have ever given up on a nuclear criticality calculation and terminated it because it took so long to converge, you might find this thesis of interest. The author develops three methods for improving the fission source convergence in nuclear criticality calculations for physical systems with high dominance ratios for which convergence is slow. The Fission Matrix Acceleration Method and the Fission Diffusion Synthetic Acceleration (FDSA) Method are acceleration methods that speed fission source convergence for both Monte Carlo and deterministic methods. The third method is a hybrid Monte Carlo method that also converges for difficult problems where the unaccelerated Monte Carlo method fails. The author tested the feasibility of all three methods in a test bed consisting of idealized problems. He has successfully accelerated fission source convergence in both deterministic and Monte Carlo criticality calculations. By filtering statistical noise, he has incorporated deterministic attributes into the Monte Carlo calculations in order to speed their source convergence. He has used both the fission matrix and a diffusion approximation to perform unbiased accelerations. The Fission Matrix Acceleration method has been implemented in the production code MCNP and successfully applied to a real problem. When the unaccelerated calculations are unable to converge to the correct solution, they cannot be accelerated in an unbiased fashion. A Hybrid Monte Carlo method weds Monte Carlo and a modified diffusion calculation to overcome these deficiencies. The Hybrid method additionally possesses reduced statistical errors.

  15. Synthetic Dataset To Benchmark Global Tomographic Methods

    Science.gov (United States)

    Qin, Yilong; Capdeville, Yann; Maupin, Valerie; Montagner, Jean-Paul

    2006-11-01

    A new set of global synthetic seismograms calculated in a three-dimensional (3-D), heterogeneous, anisotropic, anelastic model of the Earth using the spectral element method has been released by the European network SPICE (Seismic Wave Propagation and Imaging in Complex Media: a European Network). The set consists of 7424 three-component records with a minimum period of 32 seconds, a sampling rate of one second, and a duration of 10,500 seconds. The aim of this synthetic data set is to conduct a blind test of existing global tomographic methods based on long-period data, in order to test how current imaging techniques are limited by approximations in theory and by the inadequacy of data quality and coverage.

  16. Effectiveness of a consistently formulated diffusion-synthetic acceleration differencing approach

    International Nuclear Information System (INIS)

    Khalil, H.

    1988-01-01

    A consistently formulated differencing approach is applied to the diffusion-synthetic acceleration of discrete ordinates calculations based on various spatial differencing schemes. The diffusion ''coupling'' equations derived for each scheme are contrasted to conventional coupling relations and are shown to permit derivation of either point- or box-centered diffusion difference equations. The resulting difference equations are shown to be mathematically equivalent, in slab geometry, to equations derived by applying Larsen's four-step procedure to the S/sub 2/ equations. Fourier stability analysis of the acceleration method applied to slab model problems is used to demonstrate that, for any S/sub n/ differencing scheme (a) the upper bound on the spectral radius of the method occurs in the fine-mesh limit and equals that of the spatially continuous case (0.22466), and (b) the spectral radius decreases with increasing mesh size to an asymptotic value <0.13135. This model problem performance is somewhat superior to that of Larsen's approach, for which the spectral radius is bounded by 0.25 in the wide-mesh limit. Numerical results of multidimensional, heterogeneous, scattering-dominated problems are also presented to demonstrate the rapid convergence of accelerated discrete ordinates calculations using various spatial differencing schemes

  17. Fourier analysis of a new P1 synthetic acceleration for Sn transport equations

    International Nuclear Information System (INIS)

    Turcksin, B.; Ragusa, J. C.

    2010-10-01

    In this work, is derived a new P1 synthetic acceleration scheme (P1SA) for the S N transport equation and analyze its convergence properties through the means of a Fourier analysis. The Fourier analysis is carried out for both continuous (i.e., not spatially discretized) S N equations and linear discontinuous Fem discretization. We show, thanks to the continuous analysis, that the scheme is unstable when the anisotropy is important (μ - >0.5). However, the discrete analysis shows that when cells are large in comparison to the mean free path, the spectral radius decreases and the acceleration scheme becomes effective, even for highly anisotropic scattering. In charged particles transport, scattering is highly anisotropic and mean free paths are very small and, thus, this scheme could be of interest. To use the P1SA when cells are small and anisotropy is important, the scheme is modified by altering the update of the accelerated flux or by using either K transport sweeps before the application of P1SA. The update scheme performs well as long as μ - - ≥0.9, the modified update scheme is unstable. The multiple transport sweeps scheme is convergent with an arbitrary μ - but the spectral radius increases when scattering is isotropic. When anisotropic increases, the frequency of use of the acceleration scheme needs to be decreased. Even if the P1SA is used less often, the spectral radius is significantly smaller when compared with a method that does not use it for high anisotropy (μ - ≥0.5). It is interesting to notice that using P1SA every two iterations gives the same spectral radius than the update method when μ - ≥0.5 but it is much less efficient when μ - <0.5. (Author)

  18. Accelerated Test Method for Corrosion Protective Coatings

    Data.gov (United States)

    National Aeronautics and Space Administration — This project seeks to develop a new accelerated corrosion test method that predicts the long-term corrosion protection performance of spaceport structure coatings as...

  19. Fourier analysis of parallel block-Jacobi splitting with transport synthetic acceleration in two-dimensional geometry

    International Nuclear Information System (INIS)

    Rosa, M.; Warsa, J. S.; Chang, J. H.

    2007-01-01

    A Fourier analysis is conducted in two-dimensional (2D) Cartesian geometry for the discrete-ordinates (SN) approximation of the neutron transport problem solved with Richardson iteration (Source Iteration) and Richardson iteration preconditioned with Transport Synthetic Acceleration (TSA), using the Parallel Block-Jacobi (PBJ) algorithm. The results for the un-accelerated algorithm show that convergence of PBJ can degrade, leading in particular to stagnation of GMRES(m) in problems containing optically thin sub-domains. The results for the accelerated algorithm indicate that TSA can be used to efficiently precondition an iterative method in the optically thin case when implemented in the 'modified' version MTSA, in which only the scattering in the low order equations is reduced by some non-negative factor β<1. (authors)

  20. New Synthetic Methods for Hypericum Natural Products

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Insik [Iowa State Univ., Ames, IA (United States)

    2006-01-01

    Organic chemistry has served as a solid foundation for interdisciplinary research areas, such as molecular biology and medicinal chemistry. An understanding of the biological activities and structural elucidations of natural products can lead to the development of clinically valuable therapeutic options. The advancements of modern synthetic methodologies allow for more elaborate and concise natural product syntheses. The theme of this study centers on the synthesis of natural products with particularly challenging structures and interesting biological activities. The synthetic expertise developed here will be applicable to analog syntheses and to other research problems.

  1. Discontinuous diffusion synthetic acceleration for Sn transport on 2D arbitrary polygonal meshes

    International Nuclear Information System (INIS)

    Turcksin, Bruno; Ragusa, Jean C.

    2014-01-01

    In this paper, a Diffusion Synthetic Acceleration (DSA) technique applied to the S n radiation transport equation is developed using Piece-Wise Linear Discontinuous (PWLD) finite elements on arbitrary polygonal grids. The discretization of the DSA equations employs an Interior Penalty technique, as is classically done for the stabilization of the diffusion equation using discontinuous finite element approximations. The penalty method yields a system of linear equations that is Symmetric Positive Definite (SPD). Thus, solution techniques such as Preconditioned Conjugate Gradient (PCG) can be effectively employed. Algebraic MultiGrid (AMG) and Symmetric Gauss–Seidel (SGS) are employed as conjugate gradient preconditioners for the DSA system. AMG is shown to be significantly more efficient than SGS. Fourier analyses are carried out and we show that this discontinuous finite element DSA scheme is always stable and effective at reducing the spectral radius for iterative transport solves, even for grids with high-aspect ratio cells. Numerical results are presented for different grid types: quadrilateral, hexagonal, and polygonal grids as well as grids with local mesh adaptivity

  2. Validated method for the detection and quantitation of synthetic ...

    African Journals Online (AJOL)

    Validated method for the detection and quantitation of synthetic cannabinoids in whole blood and urine, and its application to postmortem cases in Johannesburg, South ... A LC-HRMS (liquid chromatography coupled with high resolution mass spectrometry) method for the detection and quantitation of several synthetic ...

  3. Accelerated Learning: Madness with a Method.

    Science.gov (United States)

    Zemke, Ron

    1995-01-01

    Accelerated learning methods have evolved into a variety of holistic techniques that involve participants in the learning process and overcome negative attitudes about learning. These components are part of the mix: the brain, learning environment, music, imaginative activities, suggestion, positive mental state, the arts, multiple intelligences,…

  4. Numerical solution of the equation of neutrons transport on plane geometry by analytical schemes using acceleration by synthetic diffusion

    International Nuclear Information System (INIS)

    Alonso-Vargas, G.

    1991-01-01

    A computer program has been developed which uses a technique of synthetic acceleration by diffusion by analytical schemes. Both in the diffusion equation as in that of transport, analytical schemes were used which allowed a substantial time saving in the number of iterations required by source iteration method to obtain the K e ff. The program developed ASD (Synthetic Diffusion Acceleration) by diffusion was written in FORTRAN and can be executed on a personal computer with a hard disc and mathematical O-processor. The program is unlimited as to the number of regions and energy groups. The results obtained by the ASD program for K e ff is nearly completely concordant with those of obtained utilizing the ANISN-PC code for different analytical type problems in this work. The ASD program allowed obtention of an approximate solution of the neutron transport equation with a relatively low number of internal reiterations with good precision. One of its applications would be in the direct determinations of axial distribution neutronic flow in a fuel assembly as well as in the obtention of the effective multiplication factor. (Author)

  5. Evolutionary optimization methods for accelerator design

    Science.gov (United States)

    Poklonskiy, Alexey A.

    Many problems from the fields of accelerator physics and beam theory can be formulated as optimization problems and, as such, solved using optimization methods. Despite growing efficiency of the optimization methods, the adoption of modern optimization techniques in these fields is rather limited. Evolutionary Algorithms (EAs) form a relatively new and actively developed optimization methods family. They possess many attractive features such as: ease of the implementation, modest requirements on the objective function, a good tolerance to noise, robustness, and the ability to perform a global search efficiently. In this work we study the application of EAs to problems from accelerator physics and beam theory. We review the most commonly used methods of unconstrained optimization and describe the GATool, evolutionary algorithm and the software package, used in this work, in detail. Then we use a set of test problems to assess its performance in terms of computational resources, quality of the obtained result, and the tradeoff between them. We justify the choice of GATool as a heuristic method to generate cutoff values for the COSY-GO rigorous global optimization package for the COSY Infinity scientific computing package. We design the model of their mutual interaction and demonstrate that the quality of the result obtained by GATool increases as the information about the search domain is refined, which supports the usefulness of this model. We Giscuss GATool's performance on the problems suffering from static and dynamic noise and study useful strategies of GATool parameter tuning for these and other difficult problems. We review the challenges of constrained optimization with EAs and methods commonly used to overcome them. We describe REPA, a new constrained optimization method based on repairing, in exquisite detail, including the properties of its two repairing techniques: REFIND and REPROPT. We assess REPROPT's performance on the standard constrained

  6. Spectral analysis of an algebraic collapsing acceleration for the characteristics method

    International Nuclear Information System (INIS)

    Le Tellier, R.; Hebert, A.

    2005-01-01

    A spectral analysis of a diffusion synthetic acceleration called Algebraic Collapsing Acceleration (ACA) was carried out in the context of the characteristics method to solve the neutron transport equation. Two analysis were performed in order to assess the ACA performances. Both a standard Fourier analysis in a periodic and infinite slab-geometry and a direct spectral analysis for a finite slab-geometry were investigated. In order to evaluate its performance, ACA was compared with two competing techniques used to accelerate the convergence of the characteristics method, the Self-Collision Re-balancing technique and the Asymptotic Synthetic Acceleration. In the restricted framework of 1-dimensional slab-geometries, we conclude that ACA offers a good compromise between the reduction of the spectral radius of the iterative matrix and the resources to construct, store and solve the corrective system. A comparison on a monoenergetic 2-dimensional benchmark was performed and tends to confirm these conclusions. (authors)

  7. Efficient analysis methods in synthetic biology.

    Science.gov (United States)

    Madsen, Curtis; Myers, Chris; Roehner, Nicholas; Winstead, Chris; Zhang, Zhen

    2015-01-01

    This chapter describes new analysis and verification techniques for synthetic genetic circuits. In particular, it applies stochastic model checking techniques to models of genetic circuits in order to ensure that they behave correctly and are as robust as possible for a variety of different inputs and parameter settings. In addition to stochastic model checking, this chapter proposes new variants to the incremental stochastic simulation algorithm (iSSA) that are capable of presenting a researcher with a simulation trace of the typical behavior of the system. Before the development of this algorithm, discerning this information was extremely error-prone as it involved performing many simulations and attempting to wade through the massive amounts of data. This algorithm greatly aids researchers in designing genetic circuits as it efficiently shows the researcher the most likely behavior of the circuit. Both the iSSA and stochastic model checking can be used in concert to give a researcher the likelihood that the system exhibits its most typical behavior, as well as, non-typical behaviors. This methodology is applied to several genetic circuits leading to new understanding of the effects of various parameters on the behavior of these circuits.

  8. Acceleration methods and models in Sn calculations

    International Nuclear Information System (INIS)

    Sbaffoni, M.M.; Abbate, M.J.

    1984-01-01

    In some neutron transport problems solved by the discrete ordinate method, it is relatively common to observe some particularities as, for example, negative fluxes generation, slow and insecure convergences and solution instabilities. The commonly used models for neutron flux calculation and acceleration methods included in the most used codes were analyzed, in face of their use in problems characterized by a strong upscattering effect. Some special conclusions derived from this analysis are presented as well as a new method to perform the upscattering scaling for solving the before mentioned problems in this kind of cases. This method has been included in the DOT3.5 code (two dimensional discrete ordinates radiation transport code) generating a new version of wider application. (Author) [es

  9. Spatial transferability using synthetic population generation methods.

    Science.gov (United States)

    2016-04-19

    In this study, we developed a new method to transfer daily travel behavior data from one place to another. This fills a critical gap in practical : applications that need data to study behaviors but also to estimate behavioral models. The basic ingre...

  10. A Method for Synthetic Aperture Compounding

    DEFF Research Database (Denmark)

    Hansen, Jens Munk; Jensen, Jørgen Arendt

    2010-01-01

    and the effect is quantized by speckle statistics and by computing contrast-to-noise ratios (CNR) from the resulting images. The method is validated using Field II simulations for a 7 MHz, =2-pitch transducer with 192 elements with 64 elements active for each scan line. Circular regions (cysts) with a diameter...... of 5 mm and scattering levels ranging from -3 to -12 dB relative to the background are imaged at 2 depths. Compound images composed of 1-5 images with an angular separation of 2 degrees are constructed and for the cysts at -3, -6, -9, and -12 dB, a CNR of -0.43, -1.11, -1.44, and -1.91 dB are obtained...

  11. A SPICE synthetic dataset to benchmark global tomographic methods

    Science.gov (United States)

    Qin, Y.; Capdeville, Y.; Maupin, V.; Montagner, J.

    2005-12-01

    The different existing global tomographic methods result in different models of the Earth. Within SPICE (Seismic wave Propagation and Imaging in Complex media: a European network), we have decided to perform a benchmark experiment of global tomographic techniques. A global model has been constructed. It includes 3D heterogeneities in velocity, anisotropy and attenuation, as well as topography of discontinuities. Simplified versions of the model will also be used. Synthetic seismograms will be generated at low frequency by the Spectral Element Method, for a realistic distribution of sources and stations. The synthetic seismograms will be made available to the scientific community at the SPICE website www.spice-rtn.org. Any group wishing to test his tomographic algorithm is encouraged to download the synthetic data.

  12. Scalable fast multipole accelerated vortex methods

    KAUST Repository

    Hu, Qi

    2014-05-01

    The fast multipole method (FMM) is often used to accelerate the calculation of particle interactions in particle-based methods to simulate incompressible flows. To evaluate the most time-consuming kernels - the Biot-Savart equation and stretching term of the vorticity equation, we mathematically reformulated it so that only two Laplace scalar potentials are used instead of six. This automatically ensuring divergence-free far-field computation. Based on this formulation, we developed a new FMM-based vortex method on heterogeneous architectures, which distributed the work between multicore CPUs and GPUs to best utilize the hardware resources and achieve excellent scalability. The algorithm uses new data structures which can dynamically manage inter-node communication and load balance efficiently, with only a small parallel construction overhead. This algorithm can scale to large-sized clusters showing both strong and weak scalability. Careful error and timing trade-off analysis are also performed for the cutoff functions induced by the vortex particle method. Our implementation can perform one time step of the velocity+stretching calculation for one billion particles on 32 nodes in 55.9 seconds, which yields 49.12 Tflop/s.

  13. Benefits of EMU Participation : Estimates using the Synthetic Control Method

    NARCIS (Netherlands)

    Verstegen, Loes; van Groezen, Bas; Meijdam, Lex

    2017-01-01

    This paper investigates quantitatively the benefits from participation in the Economic and Monetary Union for individual Euro area countries. Using the synthetic control method, we estimate how real GDP per capita would have developed for the EMU member states, if those countries had not joined the

  14. Nonlinear dimensionality reduction methods for synthetic biology biobricks' visualization.

    Science.gov (United States)

    Yang, Jiaoyun; Wang, Haipeng; Ding, Huitong; An, Ning; Alterovitz, Gil

    2017-01-19

    Visualizing data by dimensionality reduction is an important strategy in Bioinformatics, which could help to discover hidden data properties and detect data quality issues, e.g. data noise, inappropriately labeled data, etc. As crowdsourcing-based synthetic biology databases face similar data quality issues, we propose to visualize biobricks to tackle them. However, existing dimensionality reduction methods could not be directly applied on biobricks datasets. Hereby, we use normalized edit distance to enhance dimensionality reduction methods, including Isomap and Laplacian Eigenmaps. By extracting biobricks from synthetic biology database Registry of Standard Biological Parts, six combinations of various types of biobricks are tested. The visualization graphs illustrate discriminated biobricks and inappropriately labeled biobricks. Clustering algorithm K-means is adopted to quantify the reduction results. The average clustering accuracy for Isomap and Laplacian Eigenmaps are 0.857 and 0.844, respectively. Besides, Laplacian Eigenmaps is 5 times faster than Isomap, and its visualization graph is more concentrated to discriminate biobricks. By combining normalized edit distance with Isomap and Laplacian Eigenmaps, synthetic biology biobircks are successfully visualized in two dimensional space. Various types of biobricks could be discriminated and inappropriately labeled biobricks could be determined, which could help to assess crowdsourcing-based synthetic biology databases' quality, and make biobricks selection.

  15. GPU-accelerated two dimensional synthetic aperture focusing for photoacoustic microscopy

    Science.gov (United States)

    Liu, Siyu; Feng, Xiaohua; Gao, Fei; Jin, Haoran; Zhang, Ruochong; Luo, Yunqi; Zheng, Yuanjin

    2018-02-01

    Acoustic resolution photoacoustic microscopy (AR-PAM) generally suffers from limited depth of focus, which had been extended by synthetic aperture focusing techniques (SAFTs). However, for three dimensional AR-PAM, current one dimensional (1D) SAFT and its improved version like cross-shaped SAFT do not provide isotropic resolution in the lateral direction. The full potential of the SAFT remains to be tapped. To this end, two dimensional (2D) SAFT with fast computing architecture is proposed in this work. Explained by geometric modeling and Fourier acoustics theories, 2D-SAFT provide the narrowest post-focusing capability, thus to achieve best lateral resolution. Compared with previous 1D-SAFT techniques, the proposed 2D-SAFT improved the lateral resolution by at least 1.7 times and the signal-to-noise ratio (SNR) by about 10 dB in both simulation and experiments. Moreover, the improved 2D-SAFT algorithm is accelerated by a graphical processing unit that reduces the long period of reconstruction to only a few seconds. The proposed 2D-SAFT is demonstrated to outperform previous reported 1D SAFT in the aspects of improving the depth of focus, imaging resolution, and SNR with fast computational efficiency. This work facilitates future studies on in vivo deeper and high-resolution photoacoustic microscopy beyond several centimeters.

  16. GPU-accelerated two dimensional synthetic aperture focusing for photoacoustic microscopy

    Directory of Open Access Journals (Sweden)

    Siyu Liu

    2018-02-01

    Full Text Available Acoustic resolution photoacoustic microscopy (AR-PAM generally suffers from limited depth of focus, which had been extended by synthetic aperture focusing techniques (SAFTs. However, for three dimensional AR-PAM, current one dimensional (1D SAFT and its improved version like cross-shaped SAFT do not provide isotropic resolution in the lateral direction. The full potential of the SAFT remains to be tapped. To this end, two dimensional (2D SAFT with fast computing architecture is proposed in this work. Explained by geometric modeling and Fourier acoustics theories, 2D-SAFT provide the narrowest post-focusing capability, thus to achieve best lateral resolution. Compared with previous 1D-SAFT techniques, the proposed 2D-SAFT improved the lateral resolution by at least 1.7 times and the signal-to-noise ratio (SNR by about 10 dB in both simulation and experiments. Moreover, the improved 2D-SAFT algorithm is accelerated by a graphical processing unit that reduces the long period of reconstruction to only a few seconds. The proposed 2D-SAFT is demonstrated to outperform previous reported 1D SAFT in the aspects of improving the depth of focus, imaging resolution, and SNR with fast computational efficiency. This work facilitates future studies on in vivo deeper and high-resolution photoacoustic microscopy beyond several centimeters.

  17. Synthetic data. A proposed method for applied risk management

    OpenAIRE

    Carbajal De Nova, Carolina

    2017-01-01

    The proposed method attempts to contribute towards the econometric and simulation applied risk management literature. It consists on an algorithm to construct synthetic data and risk simulation econometric models, supported by a set of behavioral assumptions. This algorithm has the advantage of replicating natural phenomena and uncertainty events in a short period of time. These features convey economically low costs besides computational efficiency. An application for wheat farmers is develo...

  18. Systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators

    Science.gov (United States)

    Grisham, Larry R

    2013-12-17

    The present invention provides systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators. Advantageously, the systems and methods of the present invention improve the practically obtainable performance of these electrostatic accelerators by addressing, among other things, voltage holding problems and conditioning issues. The problems and issues are addressed by flowing electric currents along these accelerator electrodes to produce magnetic fields that envelope the accelerator electrodes and their support structures, so as to prevent very low energy electrons from leaving the surfaces of the accelerator electrodes and subsequently picking up energy from the surrounding electric field. In various applications, this magnetic insulation must only produce modest gains in voltage holding capability to represent a significant achievement.

  19. A statistical comparison of accelerated concrete testing methods

    Directory of Open Access Journals (Sweden)

    Denny Meyer

    1997-01-01

    Full Text Available Accelerated curing results, obtained after only 24 hours, are used to predict the 28 day strength of concrete. Various accelerated curing methods are available. Two of these methods are compared in relation to the accuracy of their predictions and the stability of the relationship between their 24 hour and 28 day concrete strength. The results suggest that Warm Water accelerated curing is preferable to Hot Water accelerated curing of concrete. In addition, some other methods for improving the accuracy of predictions of 28 day strengths are suggested. In particular the frequency at which it is necessary to recalibrate the prediction equation is considered.

  20. Delayless acceleration measurement method for motion control applications

    Energy Technology Data Exchange (ETDEWEB)

    Vaeliviita, S.; Ovaska, S.J. [Helsinki University of Technology, Otaniemi (Finland). Institute of Intelligent Power Electronics

    1997-12-31

    Delayless and accurate sensing of angular acceleration can improve the performance of motion control in motor drives. Acceleration control is, however, seldom implemented in practical drive systems due to prohibitively high costs or unsatisfactory results of most acceleration measurement methods. In this paper we propose an efficient and accurate acceleration measurement method based on direct differentiation of the corresponding velocity signal. Polynomial predictive filtering is used to smooth the resulting noisy signal without delay. This type of prediction is justified by noticing that a low-degree polynomial can usually be fitted into the primary acceleration curve. No additional hardware is required to implement the procedure if the velocity signal is already available. The performance of the acceleration measurement method is evaluated by applying it to a demanding motion control application. (orig.) 12 refs.

  1. Synthetic

    Directory of Open Access Journals (Sweden)

    Anna Maria Manferdini

    2010-06-01

    Full Text Available Traditionally materials have been associated with a series of physical properties that can be used as inputs to production and manufacturing. Recently we witnessed an interest in materials considered not only as ‘true matter’, but also as new breeds where geometry, texture, tooling and finish are able to provoke new sensations when they are applied to a substance. These artificial materials can be described as synthetic because they are the outcome of various qualities that are not necessarily true to the original matter, but they are the combination of two or more parts, whether by design or by natural processes. The aim of this paper is to investigate the potential of architectural surfaces to produce effects through the invention of new breeds of artificial matter, using micro-scale details derived from Nature as an inspiration.

  2. Design of synthetic soil images using the Truncated Multifractal method

    Science.gov (United States)

    Sotoca, Juan J. Martin; Saa-Requejo, Antonio; López de Herrera, Juan; Grau, Juan B.

    2017-04-01

    The use of synthetic images in soils is an increasingly used resource when comparing different segmentation methods. This type of images can simulate features of the real soil images. We can find examples of 2D and 3D synthetic soil images in the studies by Zhang (2001), Schlüter et al. (2010) and Wang et al. (2011). The aim of this presentation is to show an improved version of the Truncated Multifractal method (TMM) which was initially introduced by Martín-Sotoca et al. (2016a, 2016b). The TMM is able to construct a 3D synthetic soil image that is composed of a known air-filled pore space and a background space, which includes, as a novelty, a pebble space. The pebble space simulates the pebbles or granules of high intensity that typically appear in computed tomography (CT) soil images. The TMM can simulate the two main characteristics of the CT soil images: the scaling nature of the pore space and the low contrast at the solid/pore interface with non-bimodal greyscale value histograms. In this presentation we introduce some new components which improve the similitude between real and synthetic CT soil images. REFERENCES Martín-Sotoca, J.J., Saa-Requejo, A., Grau, J.B. and Tarquis, A.M. (2016a). New segmentation method based on fractal properties using singularity maps. Geoderma, doi: 10.1016/j.geoderma.2016.09.005 Martín-Sotoca, J.J., Saa-Requejo, A., Grau, J.B., Tarquis, A.M. (2016b). Local 3D segmentation of soil pore space based on fractal properties using singularity maps. Geoderma, doi: 10.1016/j.geoderma.2016.11.029 Schlüter, S., Weller, U., Vogel, H.J., (2010). Thresholding of X-ray microtomography images of soil using gradient masks. Comput. Geosci. 36, 1246-1251 Wang, W., Kravchenko, A.N., Smucker, A.J.M., Rivers, M.L. (2011). Comparison of image segmentation methods in simulated 2D and 3D microtomographic images of soil aggregates. Geoderma, 162, 231-241 Zhang, Y.J. (2001). A review of recent evaluation methods for image segmentation

  3. A synthetic method of solar spectrum based on LED

    Science.gov (United States)

    Wang, Ji-qiang; Su, Shi; Zhang, Guo-yu; Zhang, Jian

    2017-10-01

    A synthetic method of solar spectrum which based on the spectral characteristics of the solar spectrum and LED, and the principle of arbitrary spectral synthesis was studied by using 14 kinds of LED with different central wavelengths.The LED and solar spectrum data were selected by Origin Software firstly, then calculated the total number of LED for each center band by the transformation relation between brightness and illumination and Least Squares Curve Fit in Matlab.Finally, the spectrum curve of AM1.5 standard solar spectrum was obtained. The results met the technical indexes of the solar spectrum matching with ±20% and the solar constant with >0.5.

  4. Support subspaces method for synthetic aperture radar automatic target recognition

    Directory of Open Access Journals (Sweden)

    Vladimir Fursov

    2016-09-01

    Full Text Available This article offers a new object recognition approach that gives high quality using synthetic aperture radar images. The approach includes image preprocessing, clustering and recognition stages. At the image preprocessing stage, we compute the mass centre of object images for better image matching. A conjugation index of a recognition vector is used as a distance function at clustering and recognition stages. We suggest a construction of the so-called support subspaces, which provide high recognition quality with a significant dimension reduction. The results of the experiments demonstrate that the proposed method provides higher recognition quality (97.8% than such methods as support vector machine (95.9%, deep learning based on multilayer auto-encoder (96.6% and adaptive boosting (96.1%. The proposed method is stable for objects processed from different angles.

  5. Phase-of-flight method for setting the accelerating fields in the ion linear accelerator

    International Nuclear Information System (INIS)

    Dvortsov, S.V.; Lomize, L.G.

    1983-01-01

    For setting amplitudes and phases of accelerating fields in multiresonator ion accelerators presently Δt-procedure is used. The determination and setting of two unknown parameters of RF-field (amplitude and phase) in n-resonator is made according to the two increments of particle time-of-flight, measured experimentally: according to the change of the particle time-of-flight Δt 1 in the n-resonator, during the field switching in the resonator, and according to the change of Δt 2 of the time-of-flight in (n+1) resonator without RF-field with the switching of accelerating field in the n-resonator. When approaching the accelerator exit the particle energy increases, relative energy increment decreases and the accuracy of setting decreases. To enchance the accuracy of accelerating fields setting in a linear ion accelerator a phase-of-flight method is developed, in which for the setting of accelerating fields the measured time-of-flight increment Δt only in one resonator is used (the one in which the change of amplitude and phase is performed). Results of simulation of point bunch motion in the IYaI AN USSR linear accelerator are presented

  6. Synthetic Organic Electrochemical Methods Since 2000: On the Verge of a Renaissance.

    Science.gov (United States)

    Yan, Ming; Kawamata, Yu; Baran, Phil S

    2017-11-08

    Electrochemistry represents one of the most intimate ways of interacting with molecules. This review discusses advances in synthetic organic electrochemistry since 2000. Enabling methods and synthetic applications are analyzed alongside innate advantages as well as future challenges of electroorganic chemistry.

  7. Accelerated Test Method for Corrosion Protective Coatings Project

    Science.gov (United States)

    Falker, John; Zeitlin, Nancy; Calle, Luz

    2015-01-01

    This project seeks to develop a new accelerated corrosion test method that predicts the long-term corrosion protection performance of spaceport structure coatings as accurately and reliably as current long-term atmospheric exposure tests. This new accelerated test method will shorten the time needed to evaluate the corrosion protection performance of coatings for NASA's critical ground support structures. Lifetime prediction for spaceport structure coatings has a 5-year qualification cycle using atmospheric exposure. Current accelerated corrosion tests often provide false positives and negatives for coating performance, do not correlate to atmospheric corrosion exposure results, and do not correlate with atmospheric exposure timescales for lifetime prediction.

  8. Generation of synthetic flood hydrographs by hydrological donors (SHYDONHY method)

    Science.gov (United States)

    Paquet, Emmanuel

    2017-04-01

    For the design of hydraulic infrastructures like dams, a design hydrograph is required in most of the cases. Some of its features (e.g. peak value, duration, volume) corresponding to a given return period are computed thanks to a wide range of methods: historical records, mono or multivariate statistical analysis, stochastic simulation, etc. Then various methods have been proposed to construct design hydrographs having such characteristics, ranging from traditional unit-hydrograph to statistical methods (Yue et al., 2002). A new method to build design hydrographs (or more generally synthetic hydrographs) is introduced here, named SHYDONHY, French acronym for "Synthèse d'HYdrogrammes par DONneurs HYdrologiques". It is based on an extensive database of 100 000 flood hydrographs recorded at hourly time-step on 1300 gauging stations in France and Switzerland, covering a wide range of catchment size and climatology. For each station, an average of two hydrographs per year of record has been selected by a peak-over-threshold (POT) method with independence criteria (Lang et al., 1999). This sampling ensures that only hydrographs of intense floods are gathered in the dataset. For a given catchment, where few or no hydrograph is available at the outlet, a sub-set of 10 "donor stations" is selected within the complete dataset, considering several criteria: proximity, size, mean annual values and regimes for both total runoff and POT-selected floods. This sub-set of stations (and their corresponding flood hydrographs) will allow to: • Estimate a characteristic duration of flood hydrographs (e.g. duration for which the discharge is above 50% of the peak value). • For a given duration (e.g. one day), estimate the average peak-to- volume ratio of floods. • For a given duration and peak-to-volume ratio, generation of a synthetic reference hydrograph by combining appropriate hydrographs of the sub-set. • For a given daily discharge sequence, being observed or generated

  9. A new method of improving the acceleration voltage stability of Van de Graaff accelerators

    Science.gov (United States)

    Bürger, W.; Lange, H.; Petr, V.

    2008-02-01

    The relative energy stability of Van de Graaff type ion accelerators is typically limited to some 10-4. An inexpensive possibility to improve this situation was developed at the Forschungszentrum Dresden-Rossendorf. The method refers to the relatively stable periodic pattern of the acceleration voltage fluctuation in such accelerators. Future values of that fluctuation can be predicted with a high degree of certainty and can taken into account in the belt generator control in spite of the belt convolution caused fundamental reaction delay. The microcontroller based implementation of a "predictive fluctuation compensation" improves the relative acceleration voltage short time stability by a factor of 3-6 to well below 10-4.

  10. Accelerated gradient methods for constrained image deblurring

    International Nuclear Information System (INIS)

    Bonettini, S; Zanella, R; Zanni, L; Bertero, M

    2008-01-01

    In this paper we propose a special gradient projection method for the image deblurring problem, in the framework of the maximum likelihood approach. We present the method in a very general form and we give convergence results under standard assumptions. Then we consider the deblurring problem and the generality of the proposed algorithm allows us to add a energy conservation constraint to the maximum likelihood problem. In order to improve the convergence rate, we devise appropriate scaling strategies and steplength updating rules, especially designed for this application. The effectiveness of the method is evaluated by means of a computational study on astronomical images corrupted by Poisson noise. Comparisons with standard methods for image restoration, such as the expectation maximization algorithm, are also reported.

  11. Method for accelerated aging under combined environmental stress conditions

    International Nuclear Information System (INIS)

    Gillen, K.T.

    1979-01-01

    An accelerated aging method which can be used to simulate aging in combined stress environment situations is described. It is shown how the assumptions of the method can be tested experimentally. Aging data for a chloroprene cable jacketing material in single and combined radiation and temperature environments are analyzed and it is shown that these data offer evidence for the validity of the method

  12. Method Accelerates Training Of Some Neural Networks

    Science.gov (United States)

    Shelton, Robert O.

    1992-01-01

    Three-layer networks trained faster provided two conditions are satisfied: numbers of neurons in layers are such that majority of work done in synaptic connections between input and hidden layers, and number of neurons in input layer at least as great as number of training pairs of input and output vectors. Based on modified version of back-propagation method.

  13. Method for phosphate-accelerated bioremediation

    Science.gov (United States)

    Looney, Brian B.; Lombard, Kenneth H.; Hazen, Terry C.; Pfiffner, Susan M.; Phelps, Tommy J.; Borthen, James W.

    1996-01-01

    An apparatus and method for supplying a vapor-phase nutrient to contaminated soil for in situ bioremediation. The apparatus includes a housing adapted for containing a quantity of the liquid nutrient, a conduit in fluid communication with the interior of the housing, means for causing a gas to flow through the conduit, and means for contacting the gas with the liquid so that a portion thereof evaporates and mixes with the gas. The mixture of gas and nutrient vapor is delivered to the contaminated site via a system of injection and extraction wells configured to the site. The mixture has a partial pressure of vaporized nutrient that is no greater than the vapor pressure of the liquid. If desired, the nutrient and/or the gas may be heated to increase the vapor pressure and the nutrient concentration of the mixture. Preferably, the nutrient is a volatile, substantially nontoxic and nonflammable organic phosphate that is a liquid at environmental temperatures, such as triethyl phosphate or tributyl phosphate.

  14. Synthetic methods in phase equilibria: A new apparatus and error analysis of the method

    DEFF Research Database (Denmark)

    Fonseca, José; von Solms, Nicolas

    2014-01-01

    A new apparatus for the study of high-pressure phase equilibria using a synthetic method is described. The apparatus was especially developed for the study of solubilities of gases in condensed phases, at temperatures ranging from 243 K to 353 K and pressures up to 20 MPa. The quality of the equi...

  15. Glutarimides: Biological activity, general synthetic methods and physicochemical properties

    Directory of Open Access Journals (Sweden)

    Popović-Đorđević Jelena B.

    2015-01-01

    Full Text Available Glutarimides, 2,6-dioxopiperidines are compounds that rarely occur in natural sources, but so far isolated ones exert widespread pharmacological activities, which makes them valuable as potential pharmacotherapeutics. Glutarimides act as androgen receptor antagonists, anti-inflammatory, anxiolytics, antibacterials, and tumor suppressing agents. Some synthetic glutarimide derivatives are already in use as immunosuppressive and sedative (e.g., thalidomide or anxiolytics (buspirone drugs. The wide applicability of this class of compounds, justify the interest of scientists to explore new pathways for its syntheses. General methods for synthesis of six-membered imide ring, are presented in this paper. These methods include: a reaction of dicarboxylic acids with ammonia or primary amine, b reactions of cyclization: amido-acids, diamides, dinitriles, nitrilo-acids, amido-nitriles, amido-esters, amidoacyl-chlorides or diacyl-chlorides, c adition of carbon-monoxide on a,b-unsaturated amides, d oxidation reactions, e Michael adition of active methylen compounds on methacrylamide or conjugated amides. Some of the described methods are used for closing glutarimide ring in syntheses of farmacological active compounds sesbanimide and aldose reductase inhibitors (ARI. Analyses of the geometry, as well as, the spectroscopic analyses (NMR and FT-IR of some glutarimides are presented because of their broad spectrum of pharmacological activity. To elucidate structures of glutarimides, geometrical parameters of newly synthesized tert-pentyl-1-benzyl-4-methyl-glutarimide-3-carboxylate (PBMG are analyzed and compared with the experimental data from X-ray analysis for glutarimide. Moreover, molecular electrostatic potential (MEP surface which is plotted over the optimized geometry to elucidate the reactivity of PBMG molecule is analyzed. The electronic properties of glutarimide derivatives are explained on the example of thalidomide. The Frontier Molecular Orbital

  16. Microwave Heating of Synthetic Skin Samples for Potential Treatment of Gout Using the Metal-Assisted and Microwave-Accelerated Decrystallization Technique

    OpenAIRE

    Toker, Salih; Boone-Kukoyi, Zainab; Thompson, Nishone; Ajifa, Hillary; Clement, Travis; Ozturk, Birol; Aslan, Kadir

    2016-01-01

    Physical stability of synthetic skin samples during their exposure to microwave heating was investigated to demonstrate the use of the metal-assisted and microwave-accelerated decrystallization (MAMAD) technique for potential biomedical applications. In this regard, optical microscopy and temperature measurements were employed for the qualitative and quantitative assessment of damage to synthetic skin samples during 20 s intermittent microwave heating using a monomode microwave source (at 8 G...

  17. Acceleration methods for assembly-level transport calculations

    International Nuclear Information System (INIS)

    Adams, Marvin L.; Ramone, Gilles

    1995-01-01

    A family acceleration methods for the iterations that arise in assembly-level transport calculations is presented. A single iteration in these schemes consists of a transport sweep followed by a low-order calculation which is itself a simplified transport problem. It is shown that a previously-proposed method fitting this description is unstable in two and three dimensions. It is presented a family of methods and shown that some members are unconditionally stable. (author). 8 refs, 4 figs, 4 tabs

  18. Emittance measurements of FEL accelerators using optical transition radiation methods

    International Nuclear Information System (INIS)

    Fiorito, R.B.; Rule, D.W.; Lumpkin, A.H.; Tokar, R.L.; Dowell, D.H.; Sellyey, W.C.; Lowrey, A.R.

    1991-01-01

    Measurements of the emittance of the Boeing FEL accelerator operating at 107 Mev, were performed using optical transition radiation (OTR). The results of the three measurement methods: measurement of beam spot size as a function of magnetic quadrupole focusing strength, two screen beam spot measurements, and beam spot-divergence measurements using a OTR interferometer are compared and shown to be in excellent agreement

  19. Digestive ripening: a synthetic method par excellence for core–shell ...

    Indian Academy of Sciences (India)

    persity of nanoparticles. An even more remarkable feature of digestive ripening exemplified here is, it could be exercised as a synthetic method towards vari- ous heterostructured materials like core–shell particles, nanoalloys, and nanocomposites in combination with the synthetic method, solvated metal atom dispersion.

  20. Plasma Acceleration by Rotating Magnetic Field Method using Helicon Source

    Science.gov (United States)

    Furukawa, Takeru; Shimura, Kaichi; Kuwahara, Daisuke; Shinohara, Shunjiro

    2017-10-01

    Electrodeless plasma thrusters are very promising due to no electrode damage, leading to realize further deep space exploration. As one of the important proposals, we have been concentrating on Rotating Magnetic Field (RMF) acceleration method. High-dense plasma (up to 1013 cm-3) can be generated by using a radio frequency (rf) external antenna, and also accelerated by an antenna wound around outside of a discharge tube. In this scheme, thrust increment is achieved by the axial Lorentz force caused by non linear effects. RMF penetration condition into plasma can be more satisfied than our previous experiment, by increasing RMF coil current and decreasing the RMF frequency, causing higher thrust and fuel efficiency. Measurements of AC RMF component s have been conducted to investigate the acceleration mechanism and the field penetration experimentally. This study has been partially supported by Grant-in-Aid for Scientific Research (B: 17H02995) from the Japan Society for the Promotion of Science.

  1. Brightness-temperature retrival methods in synthetic aperture radiometers

    OpenAIRE

    Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Camps Carmona, Adriano José; Duffo Ubeda, Núria; Vall-Llossera Ferran, Mercedes Magdalena

    2009-01-01

    Bightness-temperature retrieval techniques for synthetic aperture radiometers are reviewed. Three different approaches to combine measured visibility and antenna temperatures, along with instrument characterization data, into a general equation to invert are presented. Discretization and windowing techniques are briefly discussed, and formulas for reciprocal grids using rectangular and hexagonal samplings are given. Two known techniques are used to invert the equation, namel...

  2. Comparison of sampling methods for radiocarbon dating of carbonyls in air samples via accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, Matthias, E-mail: matthias.schindler@physik.uni-erlangen.de; Kretschmer, Wolfgang; Scharf, Andreas; Tschekalinskij, Alexander

    2016-05-15

    Three new methods to sample and prepare various carbonyl compounds for radiocarbon measurements were developed and tested. Two of these procedures utilized the Strecker synthetic method to form amino acids from carbonyl compounds with either sodium cyanide or trimethylsilyl cyanide. The third procedure used semicarbazide to form crystalline carbazones with the carbonyl compounds. The resulting amino acids and semicarbazones were then separated and purified using thin layer chromatography. The separated compounds were then combusted to CO{sub 2} and reduced to graphite to determine {sup 14}C content by accelerator mass spectrometry (AMS). All of these methods were also compared with the standard carbonyl compound sampling method wherein a compound is derivatized with 2,4-dinitrophenylhydrazine and then separated by high-performance liquid chromatography (HPLC).

  3. Comparison of sampling methods for radiocarbon dating of carbonyls in air samples via accelerator mass spectrometry

    Science.gov (United States)

    Schindler, Matthias; Kretschmer, Wolfgang; Scharf, Andreas; Tschekalinskij, Alexander

    2016-05-01

    Three new methods to sample and prepare various carbonyl compounds for radiocarbon measurements were developed and tested. Two of these procedures utilized the Strecker synthetic method to form amino acids from carbonyl compounds with either sodium cyanide or trimethylsilyl cyanide. The third procedure used semicarbazide to form crystalline carbazones with the carbonyl compounds. The resulting amino acids and semicarbazones were then separated and purified using thin layer chromatography. The separated compounds were then combusted to CO2 and reduced to graphite to determine 14C content by accelerator mass spectrometry (AMS). All of these methods were also compared with the standard carbonyl compound sampling method wherein a compound is derivatized with 2,4-dinitrophenylhydrazine and then separated by high-performance liquid chromatography (HPLC).

  4. Fringe counting method for synthetic phase with frequency-modulated laser diodes

    International Nuclear Information System (INIS)

    Onodera, Ribun; Sakuyama, Munechika; Ishii, Yukihiro

    2007-01-01

    Fringe counting method with laser diodes (LDs) for displacement measurement has been constructed. Two LDs are frequency modulated by mutually inverted sawtooth currents on an unbalanced two-beam interferometer. The mutually inverted sawtooth-current modulation of LDs produces interference fringe signals with opposite signs for respective wavelengths. The two fringe signals are fed to an electronic mixer to produce a synthetic fringe signal with a reduced sensitivity to the synthetic wavelength. Synthetic fringe pulses derived from the synthetic fringe signal make a fringe counting system possible for faster movement of the tested mirror

  5. A systematic design method for robust synthetic biology to satisfy design specifications.

    Science.gov (United States)

    Chen, Bor-Sen; Wu, Chih-Hung

    2009-06-30

    Synthetic biology is foreseen to have important applications in biotechnology and medicine, and is expected to contribute significantly to a better understanding of the functioning of complex biological systems. However, the development of synthetic gene networks is still difficult and most newly created gene networks are non-functioning due to intrinsic parameter uncertainties, external disturbances and functional variations of intra- and extra-cellular environments. The design method for a robust synthetic gene network that works properly in a host cell under these intrinsic parameter uncertainties and external disturbances is the most important topic in synthetic biology. In this study, we propose a stochastic model that includes parameter fluctuations and external disturbances to mimic the dynamic behaviors of a synthetic gene network in the host cell. Then, based on this stochastic model, four design specifications are introduced to guarantee that a synthetic gene network can achieve its desired steady state behavior in spite of parameter fluctuations, external disturbances and functional variations in the host cell. We propose a systematic method to select a set of appropriate design parameters for a synthetic gene network that will satisfy these design specifications so that the intrinsic parameter fluctuations can be tolerated, the external disturbances can be efficiently filtered, and most importantly, the desired steady states can be achieved. Thus the synthetic gene network can work properly in a host cell under intrinsic parameter uncertainties, external disturbances and functional variations. Finally, a design procedure for the robust synthetic gene network is developed and a design example is given in silico to confirm the performance of the proposed method. Based on four design specifications, a systematic design procedure is developed for designers to engineer a robust synthetic biology network that can achieve its desired steady state behavior

  6. A systematic design method for robust synthetic biology to satisfy design specifications

    Directory of Open Access Journals (Sweden)

    Wu Chih-Hung

    2009-06-01

    Full Text Available Abstract Background Synthetic biology is foreseen to have important applications in biotechnology and medicine, and is expected to contribute significantly to a better understanding of the functioning of complex biological systems. However, the development of synthetic gene networks is still difficult and most newly created gene networks are non-functioning due to intrinsic parameter uncertainties, external disturbances and functional variations of intra- and extra-cellular environments. The design method for a robust synthetic gene network that works properly in a host cell under these intrinsic parameter uncertainties and external disturbances is the most important topic in synthetic biology. Results In this study, we propose a stochastic model that includes parameter fluctuations and external disturbances to mimic the dynamic behaviors of a synthetic gene network in the host cell. Then, based on this stochastic model, four design specifications are introduced to guarantee that a synthetic gene network can achieve its desired steady state behavior in spite of parameter fluctuations, external disturbances and functional variations in the host cell. We propose a systematic method to select a set of appropriate design parameters for a synthetic gene network that will satisfy these design specifications so that the intrinsic parameter fluctuations can be tolerated, the external disturbances can be efficiently filtered, and most importantly, the desired steady states can be achieved. Thus the synthetic gene network can work properly in a host cell under intrinsic parameter uncertainties, external disturbances and functional variations. Finally, a design procedure for the robust synthetic gene network is developed and a design example is given in silico to confirm the performance of the proposed method. Conclusion Based on four design specifications, a systematic design procedure is developed for designers to engineer a robust synthetic biology

  7. GPU Accelerated Ultrasonic Tomography Using Propagation and Back Propagation Method

    Science.gov (United States)

    2015-09-28

    tomographic imaging algorithm using Graphic Processing Units ( GPUs ). The Compute Unified Device Architecture (CUDA) programming model is used to develop...our parallelized algorithm since the CUDA model allows the user to interact with the GPU resources more efficiently than traditional Shader methods...3. DATES COVERED (From - To) - UU UU UU UU 28-09-2015 Approved for public release; distribution is unlimited. GPU accelerated ultrasonic tomography

  8. Methods of Fire Debris Preparation for Detection of Accelerants.

    Science.gov (United States)

    Caddy, B; Smith, F P; Macy, J

    1991-06-01

    Forensic scientists use various techniques to separate accelerants from fire debris samples before instrumental identification of added fuels. Among the choices available, traditional micro-distillation, steam distillation, vacuum distillation, headspace, heated headspace, and several vapor adsorption/desorption methods provide various advantages and disadvantages. This communication reviews the development of these techniques from the 1950s and comparison studies performed. Copyright © 1991 Central Police University.

  9. CME Velocity and Acceleration Error Estimates Using the Bootstrap Method

    Science.gov (United States)

    Michalek, Grzegorz; Gopalswamy, Nat; Yashiro, Seiji

    2017-08-01

    The bootstrap method is used to determine errors of basic attributes of coronal mass ejections (CMEs) visually identified in images obtained by the Solar and Heliospheric Observatory (SOHO) mission's Large Angle and Spectrometric Coronagraph (LASCO) instruments. The basic parameters of CMEs are stored, among others, in a database known as the SOHO/LASCO CME catalog and are widely employed for many research studies. The basic attributes of CMEs ( e.g. velocity and acceleration) are obtained from manually generated height-time plots. The subjective nature of manual measurements introduces random errors that are difficult to quantify. In many studies the impact of such measurement errors is overlooked. In this study we present a new possibility to estimate measurements errors in the basic attributes of CMEs. This approach is a computer-intensive method because it requires repeating the original data analysis procedure several times using replicate datasets. This is also commonly called the bootstrap method in the literature. We show that the bootstrap approach can be used to estimate the errors of the basic attributes of CMEs having moderately large numbers of height-time measurements. The velocity errors are in the vast majority small and depend mostly on the number of height-time points measured for a particular event. In the case of acceleration, the errors are significant, and for more than half of all CMEs, they are larger than the acceleration itself.

  10. CME Velocity and Acceleration Error Estimates Using the Bootstrap Method

    Science.gov (United States)

    Michalek, Grzegorz; Gopalswamy, Nat; Yashiro, Seiji

    2017-01-01

    The bootstrap method is used to determine errors of basic attributes of coronal mass ejections (CMEs) visually identified in images obtained by the Solar and Heliospheric Observatory (SOHO) mission's Large Angle and Spectrometric Coronagraph (LASCO) instruments. The basic parameters of CMEs are stored, among others, in a database known as the SOHO/LASCO CME catalog and are widely employed for many research studies. The basic attributes of CMEs (e.g. velocity and acceleration) are obtained from manually generated height-time plots. The subjective nature of manual measurements introduces random errors that are difficult to quantify. In many studies the impact of such measurement errors is overlooked. In this study we present a new possibility to estimate measurements errors in the basic attributes of CMEs. This approach is a computer-intensive method because it requires repeating the original data analysis procedure several times using replicate datasets. This is also commonly called the bootstrap method in the literature. We show that the bootstrap approach can be used to estimate the errors of the basic attributes of CMEs having moderately large numbers of height-time measurements. The velocity errors are in the vast majority small and depend mostly on the number of height-time points measured for a particular event. In the case of acceleration, the errors are significant, and for more than half of all CMEs, they are larger than the acceleration itself.

  11. GPU accelerated manifold correction method for spinning compact binaries

    Science.gov (United States)

    Ran, Chong-xi; Liu, Song; Zhong, Shuang-ying

    2018-04-01

    The graphics processing unit (GPU) acceleration of the manifold correction algorithm based on the compute unified device architecture (CUDA) technology is designed to simulate the dynamic evolution of the Post-Newtonian (PN) Hamiltonian formulation of spinning compact binaries. The feasibility and the efficiency of parallel computation on GPU have been confirmed by various numerical experiments. The numerical comparisons show that the accuracy on GPU execution of manifold corrections method has a good agreement with the execution of codes on merely central processing unit (CPU-based) method. The acceleration ability when the codes are implemented on GPU can increase enormously through the use of shared memory and register optimization techniques without additional hardware costs, implying that the speedup is nearly 13 times as compared with the codes executed on CPU for phase space scan (including 314 × 314 orbits). In addition, GPU-accelerated manifold correction method is used to numerically study how dynamics are affected by the spin-induced quadrupole-monopole interaction for black hole binary system.

  12. High power ring methods and accelerator driven subcritical reactor application

    Energy Technology Data Exchange (ETDEWEB)

    Tahar, Malek Haj [Univ. of Grenoble (France)

    2016-08-07

    High power proton accelerators allow providing, by spallation reaction, the neutron fluxes necessary in the synthesis of fissile material, starting from Uranium 238 or Thorium 232. This is the basis of the concept of sub-critical operation of a reactor, for energy production or nuclear waste transmutation, with the objective of achieving cleaner, safer and more efficient process than today’s technologies allow. Designing, building and operating a proton accelerator in the 500-1000 MeV energy range, CW regime, MW power class still remains a challenge nowadays. There is a limited number of installations at present achieving beam characteristics in that class, e.g., PSI in Villigen, 590 MeV CW beam from a cyclotron, SNS in Oakland, 1 GeV pulsed beam from a linear accelerator, in addition to projects as the ESS in Europe, a 5 MW beam from a linear accelerator. Furthermore, coupling an accelerator to a sub-critical nuclear reactor is a challenging proposition: some of the key issues/requirements are the design of a spallation target to withstand high power densities as well as ensure the safety of the installation. These two domains are the grounds of the PhD work: the focus is on the high power ring methods in the frame of the KURRI FFAG collaboration in Japan: upgrade of the installation towards high intensity is crucial to demonstrate the high beam power capability of FFAG. Thus, modeling of the beam dynamics and benchmarking of different codes was undertaken to validate the simulation results. Experimental results revealed some major losses that need to be understood and eventually overcome. By developing analytical models that account for the field defects, one identified major sources of imperfection in the design of scaling FFAG that explain the important tune variations resulting in the crossing of several betatron resonances. A new formula is derived to compute the tunes and properties established that characterize the effect of the field imperfections on the

  13. Synthetic Decapeptide Enhances Bacterial Clearance and Accelerates Healing in the Wounds of Restraint-Stressed Mice

    Science.gov (United States)

    2012-02-06

    showed that KSL, at concen trations up to 1 mg/ml, did not induce cell death or compromise the membrane integrity of human gingival fibroblasts...cationic antimicrobial peptide in excisional wounds. 2. Materials and methods 2.1. Animal selection For all animal experiments in this study, we selected...and psychological stress response (Padgett et al., 1998). Each mouse subjected to restraint was placed in a separate well ventilated 50 ml centrifuge

  14. Synthetic antigens, radiolabelled derivatives thereof, and methods of analysis using such derivatives

    International Nuclear Information System (INIS)

    Eisenhardt, W.A. Jr.; Hedaya, E.; Theodoropulos, S.

    1981-01-01

    This patent claim on behalf of Union Carbide Corporation, relates to a method of carrying out a competitive binding radioassay of a compound of interest in a clinical sample, using isocyanates labelled with radioiodine as synthetic antigens. (U.K.)

  15. Synthetic Methods of Quinoline Derivatives as Potent Anticancer Agents.

    Science.gov (United States)

    Sharma, Vaibhav; Mehta, Dinesh Kumar; Das, Rina

    2017-01-01

    On account of significant biological activities, quinoline derivatives have drawn more attention to the synthesis and biological activities in the search for new therapeutic agents. Several new synthetic approaches have been implemented to derive new molecules from quinoline and all the synthesized molecules showed effective anticancer activity. Some molecules are synthesized using quinolones as precursor reactant, which is another effective product of quinoline, also showing significant activity against malignant tumors. The presence of nitrogen in it and its ability to bind with enzymes like gyrase, topoisomerase II and kinase have also proven it with antitumor activity. This review encapsulates the recent advances in the synthesis and anticancer activity of Quinoline derivatives. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. Convergence acceleration of the Proteus computer code with multigrid methods

    Science.gov (United States)

    Demuren, A. O.; Ibraheem, S. O.

    1995-01-01

    This report presents the results of a study to implement convergence acceleration techniques based on the multigrid concept in the two-dimensional and three-dimensional versions of the Proteus computer code. The first section presents a review of the relevant literature on the implementation of the multigrid methods in computer codes for compressible flow analysis. The next two sections present detailed stability analysis of numerical schemes for solving the Euler and Navier-Stokes equations, based on conventional von Neumann analysis and the bi-grid analysis, respectively. The next section presents details of the computational method used in the Proteus computer code. Finally, the multigrid implementation and applications to several two-dimensional and three-dimensional test problems are presented. The results of the present study show that the multigrid method always leads to a reduction in the number of iterations (or time steps) required for convergence. However, there is an overhead associated with the use of multigrid acceleration. The overhead is higher in 2-D problems than in 3-D problems, thus overall multigrid savings in CPU time are in general better in the latter. Savings of about 40-50 percent are typical in 3-D problems, but they are about 20-30 percent in large 2-D problems. The present multigrid method is applicable to steady-state problems and is therefore ineffective in problems with inherently unstable solutions.

  17. Analytic Method to Estimate Particle Acceleration in Flux Ropes

    Science.gov (United States)

    Guidoni, S. E.; Karpen, J. T.; DeVore, C. R.

    2015-01-01

    The mechanism that accelerates particles to the energies required to produce the observed high-energy emission in solar flares is not well understood. Drake et al. (2006) proposed a kinetic mechanism for accelerating electrons in contracting magnetic islands formed by reconnection. In this model, particles that gyrate around magnetic field lines transit from island to island, increasing their energy by Fermi acceleration in those islands that are contracting. Based on these ideas, we present an analytic model to estimate the energy gain of particles orbiting around field lines inside a flux rope (2.5D magnetic island). We calculate the change in the velocity of the particles as the flux rope evolves in time. The method assumes a simple profile for the magnetic field of the evolving island; it can be applied to any case where flux ropes are formed. In our case, the flux-rope evolution is obtained from our recent high-resolution, compressible 2.5D MHD simulations of breakout eruptive flares. The simulations allow us to resolve in detail the generation and evolution of large-scale flux ropes as a result of sporadic and patchy reconnection in the flare current sheet. Our results show that the initial energy of particles can be increased by 2-5 times in a typical contracting island, before the island reconnects with the underlying arcade. Therefore, particles need to transit only from 3-7 islands to increase their energies by two orders of magnitude. These macroscopic regions, filled with a large number of particles, may explain the large observed rates of energetic electron production in flares. We conclude that this mechanism is a promising candidate for electron acceleration in flares, but further research is needed to extend our results to 3D flare conditions.

  18. Accelerators

    CERN Multimedia

    CERN. Geneva

    2001-01-01

    The talk summarizes the principles of particle acceleration and addresses problems related to storage rings like LEP and LHC. Special emphasis will be given to orbit stability, long term stability of the particle motion, collective effects and synchrotron radiation.

  19. Shelf life prediction of apple brownies using accelerated method

    Science.gov (United States)

    Pulungan, M. H.; Sukmana, A. D.; Dewi, I. A.

    2018-03-01

    The aim of this research was to determine shelf life of apple brownies. Shelf life was determined with Accelerated Shelf Life Testing method and Arrhenius equation. Experiment was conducted at 25, 35, and 45°C for 30 days. Every five days, the sample was analysed for free fatty acid (FFA), water activity (Aw), and organoleptic acceptance (flavour, aroma, and texture). The shelf life of the apple brownies based on FFA were 110, 54, and 28 days at temperature of 25, 35, and 45°C, respectively.

  20. An accelerated training method for back propagation networks

    Science.gov (United States)

    Shelton, Robert O. (Inventor)

    1993-01-01

    The principal objective is to provide a training procedure for a feed forward, back propagation neural network which greatly accelerates the training process. A set of orthogonal singular vectors are determined from the input matrix such that the standard deviations of the projections of the input vectors along these singular vectors, as a set, are substantially maximized, thus providing an optimal means of presenting the input data. Novelty exists in the method of extracting from the set of input data, a set of features which can serve to represent the input data in a simplified manner, thus greatly reducing the time/expense to training the system.

  1. A tuning method for nonuniform traveling-wave accelerating structures

    International Nuclear Information System (INIS)

    Gong Cunkui; Zheng Shuxin; Shao Jiahang; Jia Xiaoyu; Chen Huaibi

    2013-01-01

    The tuning method of uniform traveling-wave structures based on non-resonant perturbation field distribution measurement has been widely used in tuning both constant-impedance and constant-gradient structures. In this paper, the method of tuning nonuniform structures is proposed on the basis of the above theory. The internal reflection coefficient of each cell is obtained from analyzing the normalized voltage distribution. A numerical simulation of tuning process according to the coupled cavity chain theory has been done and the result shows each cell is in right phase advance after tuning. The method will be used in the tuning of a disk-loaded traveling-wave structure being developed at the Accelerator Laboratory, Tsinghua University. (authors)

  2. Microwave Heating of Synthetic Skin Samples for Potential Treatment of Gout Using the Metal-Assisted and Microwave-Accelerated Decrystallization Technique.

    Science.gov (United States)

    Toker, Salih; Boone-Kukoyi, Zainab; Thompson, Nishone; Ajifa, Hillary; Clement, Travis; Ozturk, Birol; Aslan, Kadir

    2016-11-30

    Physical stability of synthetic skin samples during their exposure to microwave heating was investigated to demonstrate the use of the metal-assisted and microwave-accelerated decrystallization (MAMAD) technique for potential biomedical applications. In this regard, optical microscopy and temperature measurements were employed for the qualitative and quantitative assessment of damage to synthetic skin samples during 20 s intermittent microwave heating using a monomode microwave source (at 8 GHz, 2-20 W) up to 120 s. The extent of damage to synthetic skin samples, assessed by the change in the surface area of skin samples, was negligible for microwave power of ≤7 W and more extensive damage (>50%) to skin samples occurred when exposed to >7 W at initial temperature range of 20-39 °C. The initial temperature of synthetic skin samples significantly affected the extent of change in temperature of synthetic skin samples during their exposure to microwave heating. The proof of principle use of the MAMAD technique was demonstrated for the decrystallization of a model biological crystal (l-alanine) placed under synthetic skin samples in the presence of gold nanoparticles. Our results showed that the size (initial size ∼850 μm) of l-alanine crystals can be reduced up to 60% in 120 s without damage to synthetic skin samples using the MAMAD technique. Finite-difference time-domain-based simulations of the electric field distribution of an 8 GHz monomode microwave radiation showed that synthetic skin samples are predicted to absorb ∼92.2% of the microwave radiation.

  3. Microwave Heating of Synthetic Skin Samples for Potential Treatment of Gout Using the Metal-Assisted and Microwave-Accelerated Decrystallization Technique

    Science.gov (United States)

    2016-01-01

    Physical stability of synthetic skin samples during their exposure to microwave heating was investigated to demonstrate the use of the metal-assisted and microwave-accelerated decrystallization (MAMAD) technique for potential biomedical applications. In this regard, optical microscopy and temperature measurements were employed for the qualitative and quantitative assessment of damage to synthetic skin samples during 20 s intermittent microwave heating using a monomode microwave source (at 8 GHz, 2–20 W) up to 120 s. The extent of damage to synthetic skin samples, assessed by the change in the surface area of skin samples, was negligible for microwave power of ≤7 W and more extensive damage (>50%) to skin samples occurred when exposed to >7 W at initial temperature range of 20–39 °C. The initial temperature of synthetic skin samples significantly affected the extent of change in temperature of synthetic skin samples during their exposure to microwave heating. The proof of principle use of the MAMAD technique was demonstrated for the decrystallization of a model biological crystal (l-alanine) placed under synthetic skin samples in the presence of gold nanoparticles. Our results showed that the size (initial size ∼850 μm) of l-alanine crystals can be reduced up to 60% in 120 s without damage to synthetic skin samples using the MAMAD technique. Finite-difference time-domain-based simulations of the electric field distribution of an 8 GHz monomode microwave radiation showed that synthetic skin samples are predicted to absorb ∼92.2% of the microwave radiation. PMID:27917407

  4. Microwave-accelerated derivatization for the simultaneous gas chromatographic-mass spectrometric analysis of natural and synthetic estrogenic steroids.

    Science.gov (United States)

    Zuo, Yuegang; Zhang, Kai; Lin, Yuejuan

    2007-05-04

    A rapid microwave-accelerated derivatization process for the GC-MS analysis of steroid estrogens, estrone (E1), 17beta-estradiol (E2), estriol (E3), 17alpha-ethynylestradiol (EE2) and mestranol (MeEE2), was developed. Under microwave irradiation, the five estrogenic hormones studied were simultaneously derivatized with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA)+trimethylchlorosilane (TMCS) in pyridine solution. Effects of irradiation time (15-120 s) and power level (240-800 W) on the yield of the derivatization were investigated. The derivatization under the irradiation of 800 W microwave for 60s produced comparable results when compared with the conventional heating process in a sand bath for 30 min at 80 degrees C in terms of derivatization yield, linearity and precision for all steroid hormones tested. The calibration curves are linear between 3.00 and 3.00 x 10(2) microg mL(-1). The square of the regression coefficients (R(2)) range from 0.979 to 1.000. The applicability of the method was evaluated on spiked river and distilled water samples at two concentrations, 25.0 and 2.00 x 10(2) ng mL(-1). The recoveries obtained by using microwave heating (60s, 800 W) were similar to those by conventional heating. When combined solid-phase extraction (SPE) with the application of the microwave-accelerated derivatization proposed here, the detection limits of 0.02-0.1 ng L(-1) for the steroid hormones have been achieved. The results demonstrated that microwave-accelerated derivatization is an efficient and suitable sample preparation method for the GC-MS analysis of estrogenic steroids.

  5. Synthetic polymers and methods of making and using the same

    Science.gov (United States)

    Daily, Michael D.; Grate, Jay W.; Mo, Kai-For

    2016-06-14

    Monomer embodiments that can be used to make polymers, such as homopolymers, heteropolymers, and that can be used in particular embodiments to make sequence-defined polymers are described. Also described are methods of making polymers using such monomer embodiments. Methods of using the polymers also are described.

  6. Nonsurgical Methods for the Acceleration of the Orthodontic Tooth Movement.

    Science.gov (United States)

    Almpani, Konstantinia; Kantarci, Alpdogan

    2016-01-01

    While acceleration of the orthodontic tooth movement by surgical techniques has been shown to be effective for decades, noninvasive and nonsurgical methods have always been preferred by both the clinicians and the patients. These techniques have ranged from application of biological molecules to innovative technologies such as resonance vibration, cyclic forces, light electrical currents, magnetic field forces, low-intensity laser irradiation and low-level light therapy. Endogenously produced biologicals have been tested based on their roles in the turnover of alveolar bone in response to orthodontic tooth movement as well as during wound healing. The premise behind this approach is that these exogenously applied compounds will mimic their counterparts produced in vivo. Meanwhile, technologies tested so far target these pathways for the acceleration of the orthodontic tooth movement. All these approaches have shown favorable outcomes with varying success. This chapter presents the current knowledge and a discussion over their limitations with an emphasis on the mechanism of action for each technique. © 2016 S. Karger AG, Basel.

  7. Simple and novel synthetic method to mixed-donor podand

    Directory of Open Access Journals (Sweden)

    Fatemeh Moradgholi

    2015-06-01

    Full Text Available An efficient method for the synthesis of new compounds of dibenzo podand containing mixed-donor atom is described. The key starting materials for these podand was successfully prepared in 92% yield from 2-aminophenol and benzaldehyde in water. The structures of these new compounds were confirmed on the basis of IR, 1H NMR and 13C NMR and Ms spectroscopic data.

  8. A Synthetic Approach to the Transfer Matrix Method in Classical and Quantum Physics

    Science.gov (United States)

    Pujol, O.; Perez, J. P.

    2007-01-01

    The aim of this paper is to propose a synthetic approach to the transfer matrix method in classical and quantum physics. This method is an efficient tool to deal with complicated physical systems of practical importance in geometrical light or charged particle optics, classical electronics, mechanics, electromagnetics and quantum physics. Teaching…

  9. Acceleration methods for multi-physics compressible flow

    Science.gov (United States)

    Peles, Oren; Turkel, Eli

    2018-04-01

    In this work we investigate the Runge-Kutta (RK)/Implicit smoother scheme as a convergence accelerator for complex multi-physics flow problems including turbulent, reactive and also two-phase flows. The flows considered are subsonic, transonic and supersonic flows in complex geometries, and also can be either steady or unsteady flows. All of these problems are considered to be a very stiff. We then introduce an acceleration method for the compressible Navier-Stokes equations. We start with the multigrid method for pure subsonic flow, including reactive flows. We then add the Rossow-Swanson-Turkel RK/Implicit smoother that enables performing all these complex flow simulations with a reasonable CFL number. We next discuss the RK/Implicit smoother for time dependent problem and also for low Mach numbers. The preconditioner includes an intrinsic low Mach number treatment inside the smoother operator. We also develop a modified Roe scheme with a corresponding flux Jacobian matrix. We then give the extension of the method for real gas and reactive flow. Reactive flows are governed by a system of inhomogeneous Navier-Stokes equations with very stiff source terms. The extension of the RK/Implicit smoother requires an approximation of the source term Jacobian. The properties of the Jacobian are very important for the stability of the method. We discuss what the chemical physics theory of chemical kinetics tells about the mathematical properties of the Jacobian matrix. We focus on the implication of the Le-Chatelier's principle on the sign of the diagonal entries of the Jacobian. We present the implementation of the method for turbulent flow. We use a two RANS turbulent model - one equation model - Spalart-Allmaras and a two-equation model - k-ω SST model. The last extension is for two-phase flows with a gas as a main phase and Eulerian representation of a dispersed particles phase (EDP). We present some examples for such flow computations inside a ballistic evaluation

  10. Generalized Coarse-Mesh Rebalance Method for Acceleration of Neutron Transport Calculations

    International Nuclear Information System (INIS)

    Yamamoto, Akio

    2005-01-01

    This paper proposes a new acceleration method for neutron transport calculations: the generalized coarse-mesh rebalance (GCMR) method. The GCMR method is a unified scheme of the traditional coarse-mesh rebalance (CMR) and the coarse-mesh finite difference (CMFD) acceleration methods. Namely, by using an appropriate acceleration factor, formulation of the GCMR method becomes identical to that of the CMR or CMFD method. This also indicates that the convergence property of the GCMR method can be controlled by the acceleration factor since the convergence properties of the CMR and CMFD methods are generally different. In order to evaluate the convergence property of the GCMR method, a linearized Fourier analysis was carried out for a one-group homogeneous medium, and the results clarified the relationship between the acceleration factor and the spectral radius. It was also shown that the spectral radius of the GCMR method is smaller than those of the CMR and CMFD methods. Furthermore, the Fourier analysis showed that when an appropriate acceleration factor was used, the spectral radius of the GCMR method did not exceed unity in this study, which was in contrast to the results of the CMR or the CMFD method. Application of the GCMR method to practical calculations will be easy when the CMFD acceleration is already adopted in a transport code. By multiplying a suitable acceleration factor to a coefficient (D FD ) of a finite difference formulation, one can improve the numerical instability of the CMFD acceleration method

  11. Accelerated aging of IG units : North American test methods

    International Nuclear Information System (INIS)

    Elmahdy, H.

    2002-01-01

    Both Canadian and American standards have been in place for decades to determine argon gas concentration in insulating glass (IG) units. Efforts are underway to harmonize the IG standards to have acceptable test methods for the durability of IG units and to implement a single certification program for both Canada and the United States. One way to test the durability and integrity of the edge seal on IG units is to subject them to accelerated aging cycles in a controlled environment. This paper summarizes the Canadian, American and the harmonized test methods used in testing the integrity of the seal and the determination of argon gas in IG units. The Canadian standard (CAN/CGSB 12.8) encompasses the following tests: initial seal of units, initial dew point, initial argon concentration, failure analysis (water immersion test), weather cycling, volatile fogging (UV), dew point measurement after weather cycling, high humidity cycling, and final argon concentration. American ASTM E773 and ASTM E774 differ from the Canadian standard in the sequence of testing and the rating of IG units, creating problems for certification of units being shipped across the border. It was noted that adopting a single certification program for Canada and the United States would bring economic benefits to both consumers and manufacturers. 7 refs., 5 figs

  12. VALU, AVX and GPU acceleration techniques for parallel FDTD methods

    CERN Document Server

    Yu, Wenhua

    2013-01-01

    This book introduces a general hardware acceleration technique that can significantly speed up FDTD simulations and their applications to engineering problems without requiring any additional hardware devices. This acceleration of complex problems can be efficient in saving both time and money and once learned these new techniques can be used repeatedly.

  13. Accelerated molecular dynamics methods: introduction and recent developments

    Energy Technology Data Exchange (ETDEWEB)

    Uberuaga, Blas Pedro [Los Alamos National Laboratory; Voter, Arthur F [Los Alamos National Laboratory; Perez, Danny [Los Alamos National Laboratory; Shim, Y [UNIV OF TOLEDO; Amar, J G [UNIV OF TOLEDO

    2009-01-01

    reaction pathways may be important, we return instead to a molecular dynamics treatment, in which the trajectory itself finds an appropriate way to escape from each state of the system. Since a direct integration of the trajectory would be limited to nanoseconds, while we are seeking to follow the system for much longer times, we modify the dynamics in some way to cause the first escape to happen much more quickly, thereby accelerating the dynamics. The key is to design the modified dynamics in a way that does as little damage as possible to the probability for escaping along a given pathway - i.e., we try to preserve the relative rate constants for the different possible escape paths out of the state. We can then use this modified dynamics to follow the system from state to state, reaching much longer times than we could reach with direct MD. The dynamics within any one state may no longer be meaningful, but the state-to-state dynamics, in the best case, as we discuss in the paper, can be exact. We have developed three methods in this accelerated molecular dynamics (AMD) class, in each case appealing to TST, either implicitly or explicitly, to design the modified dynamics. Each of these methods has its own advantages, and we and others have applied these methods to a wide range of problems. The purpose of this article is to give the reader a brief introduction to how these methods work, and discuss some of the recent developments that have been made to improve their power and applicability. Note that this brief review does not claim to be exhaustive: various other methods aiming at similar goals have been proposed in the literature. For the sake of brevity, our focus will exclusively be on the methods developed by the group.

  14. Accelerated molecular dynamics methods: introduction and recent developments

    International Nuclear Information System (INIS)

    Uberuaga, Blas Pedro; Voter, Arthur F.; Perez, Danny; Shim, Y.; Amar, J.G.

    2009-01-01

    reaction pathways may be important, we return instead to a molecular dynamics treatment, in which the trajectory itself finds an appropriate way to escape from each state of the system. Since a direct integration of the trajectory would be limited to nanoseconds, while we are seeking to follow the system for much longer times, we modify the dynamics in some way to cause the first escape to happen much more quickly, thereby accelerating the dynamics. The key is to design the modified dynamics in a way that does as little damage as possible to the probability for escaping along a given pathway - i.e., we try to preserve the relative rate constants for the different possible escape paths out of the state. We can then use this modified dynamics to follow the system from state to state, reaching much longer times than we could reach with direct MD. The dynamics within any one state may no longer be meaningful, but the state-to-state dynamics, in the best case, as we discuss in the paper, can be exact. We have developed three methods in this accelerated molecular dynamics (AMD) class, in each case appealing to TST, either implicitly or explicitly, to design the modified dynamics. Each of these methods has its own advantages, and we and others have applied these methods to a wide range of problems. The purpose of this article is to give the reader a brief introduction to how these methods work, and discuss some of the recent developments that have been made to improve their power and applicability. Note that this brief review does not claim to be exhaustive: various other methods aiming at similar goals have been proposed in the literature. For the sake of brevity, our focus will exclusively be on the methods developed by the group

  15. Real-Time Spaceborne Synthetic Aperture Radar Float-Point Imaging System Using Optimized Mapping Methodology and a Multi-Node Parallel Accelerating Technique.

    Science.gov (United States)

    Li, Bingyi; Shi, Hao; Chen, Liang; Yu, Wenyue; Yang, Chen; Xie, Yizhuang; Bian, Mingming; Zhang, Qingjun; Pang, Long

    2018-02-28

    With the development of satellite load technology and very large-scale integrated (VLSI) circuit technology, on-board real-time synthetic aperture radar (SAR) imaging systems have facilitated rapid response to disasters. A key goal of the on-board SAR imaging system design is to achieve high real-time processing performance under severe size, weight, and power consumption constraints. This paper presents a multi-node prototype system for real-time SAR imaging processing. We decompose the commonly used chirp scaling (CS) SAR imaging algorithm into two parts according to the computing features. The linearization and logic-memory optimum allocation methods are adopted to realize the nonlinear part in a reconfigurable structure, and the two-part bandwidth balance method is used to realize the linear part. Thus, float-point SAR imaging processing can be integrated into a single Field Programmable Gate Array (FPGA) chip instead of relying on distributed technologies. A single-processing node requires 10.6 s and consumes 17 W to focus on 25-km swath width, 5-m resolution stripmap SAR raw data with a granularity of 16,384 × 16,384. The design methodology of the multi-FPGA parallel accelerating system under the real-time principle is introduced. As a proof of concept, a prototype with four processing nodes and one master node is implemented using a Xilinx xc6vlx315t FPGA. The weight and volume of one single machine are 10 kg and 32 cm × 24 cm × 20 cm, respectively, and the power consumption is under 100 W. The real-time performance of the proposed design is demonstrated on Chinese Gaofen-3 stripmap continuous imaging.

  16. A Novel Method for Vertical Acceleration Noise Suppression of a Thrust-Vectored VTOL UAV

    Directory of Open Access Journals (Sweden)

    Huanyu Li

    2016-12-01

    Full Text Available Acceleration is of great importance in motion control for unmanned aerial vehicles (UAVs, especially during the takeoff and landing stages. However, the measured acceleration is inevitably polluted by severe noise. Therefore, a proper noise suppression procedure is required. This paper presents a novel method to reduce the noise in the measured vertical acceleration for a thrust-vectored tail-sitter vertical takeoff and landing (VTOL UAV. In the new procedure, a Kalman filter is first applied to estimate the UAV mass by using the information in the vertical thrust and measured acceleration. The UAV mass is then used to compute an estimate of UAV vertical acceleration. The estimated acceleration is finally fused with the measured acceleration to obtain the minimum variance estimate of vertical acceleration. By doing this, the new approach incorporates the thrust information into the acceleration estimate. The method is applied to the data measured in a VTOL UAV takeoff experiment. Two other denoising approaches developed by former researchers are also tested for comparison. The results demonstrate that the new method is able to suppress the acceleration noise substantially. It also maintains the real-time performance in the final estimated acceleration, which is not seen in the former denoising approaches. The acceleration treated with the new method can be readily used in the motion control applications for UAVs to achieve improved accuracy.

  17. A Novel Method for Vertical Acceleration Noise Suppression of a Thrust-Vectored VTOL UAV.

    Science.gov (United States)

    Li, Huanyu; Wu, Linfeng; Li, Yingjie; Li, Chunwen; Li, Hangyu

    2016-12-02

    Acceleration is of great importance in motion control for unmanned aerial vehicles (UAVs), especially during the takeoff and landing stages. However, the measured acceleration is inevitably polluted by severe noise. Therefore, a proper noise suppression procedure is required. This paper presents a novel method to reduce the noise in the measured vertical acceleration for a thrust-vectored tail-sitter vertical takeoff and landing (VTOL) UAV. In the new procedure, a Kalman filter is first applied to estimate the UAV mass by using the information in the vertical thrust and measured acceleration. The UAV mass is then used to compute an estimate of UAV vertical acceleration. The estimated acceleration is finally fused with the measured acceleration to obtain the minimum variance estimate of vertical acceleration. By doing this, the new approach incorporates the thrust information into the acceleration estimate. The method is applied to the data measured in a VTOL UAV takeoff experiment. Two other denoising approaches developed by former researchers are also tested for comparison. The results demonstrate that the new method is able to suppress the acceleration noise substantially. It also maintains the real-time performance in the final estimated acceleration, which is not seen in the former denoising approaches. The acceleration treated with the new method can be readily used in the motion control applications for UAVs to achieve improved accuracy.

  18. Monoclonal antibodies to synthetic pyrethroids and method for detecting the same

    Energy Technology Data Exchange (ETDEWEB)

    Stanker, L.H.; Vanderlaan, M.; Watkins, B.E.; Van Emon, J.M.; Bigbee, C.L.

    1992-04-28

    Methods are described for making specific monoclonal antibodies which may be used in a sensitive immunoassay for detection of synthetic pyrethroids in foods and environmental samples. Appropriate sample preparation and enzyme amplification of the immunoassay for this widely-used class of pesticides permits detection at low levels in laboratory and field tested samples. 6 figs.

  19. Monoclonal antibodies to synthetic pyrethroids and method for detecting the same

    Energy Technology Data Exchange (ETDEWEB)

    Stanker, Larry H. (Livermore, CA); Vanderlaan, Martin (Danville, CA); Watkins, Bruce E. (Livermore, CA); Van Emon, Jeanette M. (Henderson, NV); Bigbee, Carolyn L. (Livermore, CA)

    1992-01-01

    Methods are described for making specific monoclonal antibodies which may be used in a sensitive immunoassay for detection of synthetic pyrethroids in foods and environmental samples. Appropriate sample preparation and enzyme amplification of the immunoassay for this widely-used class of pesticides permits detection at low levels in laboratory and field tested samples.

  20. A method for the determination of synthetic alcohol in some alcoholic beverages

    International Nuclear Information System (INIS)

    Majerova, P.; Fiser, B.; Leseticky, L.

    2003-01-01

    While natural alcohol obtained by fermentation of sugars contains about 0.27 Bq 14 C per g carbon, synthetic spirit contains virtually no 14 C. The liquid scintillation counting method was used to analyze the beverages. The PSC cocktail was found to suit best to this purpose. The beverage samples were distilled through a short column and the 96% ethanol so obtained was measured. The fermentation ethanol-to-synthetic ethanol ratio lay within the range of 9.18-9.81. (P.A.)

  1. Demonstration recommendations for accelerated testing of concrete decontamination methods

    Energy Technology Data Exchange (ETDEWEB)

    Dickerson, K.S.; Ally, M.R.; Brown, C.H.; Morris, M.I.; Wilson-Nichols, M.J.

    1995-12-01

    A large number of aging US Department of Energy (DOE) surplus facilities located throughout the US require deactivation, decontamination, and decommissioning. Although several technologies are available commercially for concrete decontamination, emerging technologies with potential to reduce secondary waste and minimize the impact and risk to workers and the environment are needed. In response to these needs, the Accelerated Testing of Concrete Decontamination Methods project team described the nature and extent of contaminated concrete within the DOE complex and identified applicable emerging technologies. Existing information used to describe the nature and extent of contaminated concrete indicates that the most frequently occurring radiological contaminants are {sup 137}Cs, {sup 238}U (and its daughters), {sup 60}Co, {sup 90}Sr, and tritium. The total area of radionuclide-contaminated concrete within the DOE complex is estimated to be in the range of 7.9 {times} 10{sup 8} ft{sup 2}or approximately 18,000 acres. Concrete decontamination problems were matched with emerging technologies to recommend demonstrations considered to provide the most benefit to decontamination of concrete within the DOE complex. Emerging technologies with the most potential benefit were biological decontamination, electro-hydraulic scabbling, electrokinetics, and microwave scabbling.

  2. Demonstration recommendations for accelerated testing of concrete decontamination methods

    International Nuclear Information System (INIS)

    Dickerson, K.S.; Ally, M.R.; Brown, C.H.; Morris, M.I.; Wilson-Nichols, M.J.

    1995-12-01

    A large number of aging US Department of Energy (DOE) surplus facilities located throughout the US require deactivation, decontamination, and decommissioning. Although several technologies are available commercially for concrete decontamination, emerging technologies with potential to reduce secondary waste and minimize the impact and risk to workers and the environment are needed. In response to these needs, the Accelerated Testing of Concrete Decontamination Methods project team described the nature and extent of contaminated concrete within the DOE complex and identified applicable emerging technologies. Existing information used to describe the nature and extent of contaminated concrete indicates that the most frequently occurring radiological contaminants are 137 Cs, 238 U (and its daughters), 60 Co, 90 Sr, and tritium. The total area of radionuclide-contaminated concrete within the DOE complex is estimated to be in the range of 7.9 x 10 8 ft 2 or approximately 18,000 acres. Concrete decontamination problems were matched with emerging technologies to recommend demonstrations considered to provide the most benefit to decontamination of concrete within the DOE complex. Emerging technologies with the most potential benefit were biological decontamination, electro-hydraulic scabbling, electrokinetics, and microwave scabbling

  3. SPECTROPHOTOMETRIC METHOD FOR SIMULTANEOUS ESTIMATION OF TOLPERISONE HYDROCHLORIDE AND DICLOFENAC SODIUM IN SYNTHETIC MIXTURE

    OpenAIRE

    Patel Satish A; Hariyani Kaushik P

    2012-01-01

    The present manuscript describes simple, sensitive, rapid, accurate, precise and economical spectrophotometric method for the simultaneous determination of Diclofenac sodium and Tolperisone hydrochloride in bulk and synthetic mixture. The method is based on the simultaneous equations for analysis of both the drugs using methanol as solvent. Diclofenac sodium has absorbance maxima at 281 nm and Tolperisone hydrochloride has absorbance maxima at 255 nm in methanol. The linearity was obtained in...

  4. SPECTROPHOTOMETRIC METHOD FOR SIMULTANEOUS ESTIMATION OF EPERISONE HYDROCHLORIDE AND DICLOFENAC SODIUM IN SYNTHETIC MIXTURE

    OpenAIRE

    Patel Paresh U; Patel Sejal K; Patel Umang J

    2012-01-01

    The present manuscript describes simple, sensitive, rapid, accurate, precise and economical spectrophotometric method for the simultaneous determination of diclofenac sodium and Eperisone hydrochloride in bulk and synthetic mixture. The method is based on the simultaneous equations for analysis of both the drugs using methanol as solvent. Diclofenac sodium has absorbance maxima at 281 nm and Eperisone hydrochloride has absorbance maxima at 255 nm in methanol. The linearity was obtained in the...

  5. Direct coal liquefaction: general characteristics and comparison with other methods of manufacturing synthetic fuels

    Energy Technology Data Exchange (ETDEWEB)

    Legarreta, J.A.; Arias, P.L.; Cambra, J.F.; Gutierrez-Canas, C.

    1985-01-01

    Direct liquefaction has considerable advantages over other methods available for coal beneficiation by the manufacture of liquid fuels, namely: it requires a lower chemical reaction and is therefore a more efficient method which consumes less energy; it requires less stringent operating conditions which reduces equipment costs; synthetic liquid fuel is a much more concentrated form of energy than gas which makes it easier to store and transport; and liquefaction plants require less water and produce less liquid and gaseous effluents. 10 references.

  6. Systems and methods for cylindrical hall thrusters with independently controllable ionization and acceleration stages

    Science.gov (United States)

    Diamant, Kevin David; Raitses, Yevgeny; Fisch, Nathaniel Joseph

    2014-05-13

    Systems and methods may be provided for cylindrical Hall thrusters with independently controllable ionization and acceleration stages. The systems and methods may include a cylindrical channel having a center axial direction, a gas inlet for directing ionizable gas to an ionization section of the cylindrical channel, an ionization device that ionizes at least a portion of the ionizable gas within the ionization section to generate ionized gas, and an acceleration device distinct from the ionization device. The acceleration device may provide an axial electric field for an acceleration section of the cylindrical channel to accelerate the ionized gas through the acceleration section, where the axial electric field has an axial direction in relation to the center axial direction. The ionization section and the acceleration section of the cylindrical channel may be substantially non-overlapping.

  7. Development of wide area environment accelerator operation and diagnostics method

    Science.gov (United States)

    Uchiyama, Akito; Furukawa, Kazuro

    2015-08-01

    Remote operation and diagnostic systems for particle accelerators have been developed for beam operation and maintenance in various situations. Even though fully remote experiments are not necessary, the remote diagnosis and maintenance of the accelerator is required. Considering remote-operation operator interfaces (OPIs), the use of standard protocols such as the hypertext transfer protocol (HTTP) is advantageous, because system-dependent protocols are unnecessary between the remote client and the on-site server. Here, we have developed a client system based on WebSocket, which is a new protocol provided by the Internet Engineering Task Force for Web-based systems, as a next-generation Web-based OPI using the Experimental Physics and Industrial Control System Channel Access protocol. As a result of this implementation, WebSocket-based client systems have become available for remote operation. Also, as regards practical application, the remote operation of an accelerator via a wide area network (WAN) faces a number of challenges, e.g., the accelerator has both experimental device and radiation generator characteristics. Any error in remote control system operation could result in an immediate breakdown. Therefore, we propose the implementation of an operator intervention system for remote accelerator diagnostics and support that can obviate any differences between the local control room and remote locations. Here, remote-operation Web-based OPIs, which resolve security issues, are developed.

  8. Laser-driven ion acceleration: methods, challenges and prospects

    Science.gov (United States)

    Badziak, J.

    2018-01-01

    The recent development of laser technology has resulted in the construction of short-pulse lasers capable of generating fs light pulses with PW powers and intensities exceeding 1021 W/cm2, and has laid the basis for the multi-PW lasers, just being built in Europe, that will produce fs pulses of ultra-relativistic intensities ~ 1023 - 1024 W/cm2. The interaction of such an intense laser pulse with a dense target can result in the generation of collimated beams of ions of multi-MeV to GeV energies of sub-ps time durations and of extremely high beam intensities and ion fluencies, barely attainable with conventional RF-driven accelerators. Ion beams with such unique features have the potential for application in various fields of scientific research as well as in medical and technological developments. This paper provides a brief review of state-of-the art in laser-driven ion acceleration, with a focus on basic ion acceleration mechanisms and the production of ultra-intense ion beams. The challenges facing laser-driven ion acceleration studies, in particular those connected with potential applications of laser-accelerated ion beams, are also discussed.

  9. The Extrapolation-Accelerated Multilevel Aggregation Method in PageRank Computation

    Directory of Open Access Journals (Sweden)

    Bing-Yuan Pu

    2013-01-01

    Full Text Available An accelerated multilevel aggregation method is presented for calculating the stationary probability vector of an irreducible stochastic matrix in PageRank computation, where the vector extrapolation method is its accelerator. We show how to periodically combine the extrapolation method together with the multilevel aggregation method on the finest level for speeding up the PageRank computation. Detailed numerical results are given to illustrate the behavior of this method, and comparisons with the typical methods are also made.

  10. An alternative method of analysis for base accelerated dynamic response in NASTRAN

    Science.gov (United States)

    Elchuri, V.; Gallo, A. M.; Smith, G. C. C.

    1983-01-01

    An alternative method of analysis to determine the dynamic response of structures subjected to base accelerations is presented. The method is exact as opposed to the approximate technique of using unusually large masses and loads to enforce desired base accelerations. This paper presents the relevant equations to motion, ALTERs for direct and modal frequency-, random- and transient-response rigid formats, and illustrative examples.

  11. Ultrahigh impedance method to assess electrostatic accelerator performance

    Directory of Open Access Journals (Sweden)

    Nikolai R. Lobanov

    2015-06-01

    Full Text Available This paper describes an investigation of problem-solving procedures to troubleshoot electrostatic accelerators. A novel technique to diagnose issues with high-voltage components is described. The main application of this technique is noninvasive testing of electrostatic accelerator high-voltage grading systems, measuring insulation resistance, or determining the volume and surface resistivity of insulation materials used in column posts and acceleration tubes. In addition, this technique allows verification of the continuity of the resistive divider assembly as a complete circuit, revealing if an electrical path exists between equipotential rings, resistors, tube electrodes, and column post-to-tube conductors. It is capable of identifying and locating a “microbreak” in a resistor and the experimental validation of the transfer function of the high impedance energy control element. A simple and practical fault-finding procedure has been developed based on fundamental principles. The experimental distributions of relative resistance deviations (ΔR/R for both accelerating tubes and posts were collected during five scheduled accelerator maintenance tank openings during 2013 and 2014. Components with measured ΔR/R>±2.5% were considered faulty and put through a detailed examination, with faults categorized. In total, thirty four unique fault categories were identified and most would not be identifiable without the new technique described. The most common failure mode was permanent and irreversible insulator current leakage that developed after being exposed to the ambient environment. As a result of efficient in situ troubleshooting and fault-elimination techniques, the maximum values of |ΔR/R| are kept below 2.5% at the conclusion of maintenance procedures. The acceptance margin could be narrowed even further by a factor of 2.5 by increasing the test voltage from 40 V up to 100 V. Based on experience over the last two years, resistor and

  12. Application of synthetic diffusion method in the numerical solution of the equations of neutron transport in slab geometry

    International Nuclear Information System (INIS)

    Valdes Parra, J.J.

    1986-01-01

    One of the main problems in reactor physics is to determine the neutron distribution in reactor core, since knowing that, it is possible to calculate the rapidity of occurrence of different nuclear reaction inside the reactor core. Within different theories existing in nuclear reactor physics, is neutron transport the one in which equation who govern the exact behavior of neutronic distribution are developed even inside the proper neutron transport theory, there exist different methods of solution which are approximations to exact solution; still more, with the purpose to reach a more precise solution, the majority of methods have been approached to the obtention of solutions in numerical form with the aim of take the advantages of modern computers, and for this reason a great deal of effort is dedicated to numerical solution of the equations of neutron transport. In agreement with the above mentioned, in this work has been developed a computer program which uses a relatively new techniques known as 'acceleration of synthetic diffusion' which has been applied to solve the neutron transport equation with 'classical schemes of spatial integration' obtaining results with a smaller quantity of interactions, if they compare to done without using such equation (Author)

  13. The Effect of Novel Synthetic Methods and Parameters Control on Morphology of Nano-alumina Particles

    Science.gov (United States)

    Xie, Yadian; Kocaefe, Duygu; Kocaefe, Yasar; Cheng, Johnathan; Liu, Wei

    2016-05-01

    Alumina is an inorganic material, which is widely used in ceramics, catalysts, catalyst supports, ion exchange and other fields. The micromorphology of alumina determines its application in high tech and value-added industry and its development prospects. This paper gives an overview of the liquid phase synthetic method of alumina preparation, combined with the mechanism of its action. The present work focuses on the effects of various factors such as concentration, temperature, pH, additives, reaction system and methods of calcination on the morphology of alumina during its preparation.

  14. Combinatorial biosynthesis of cyclic lipopeptide antibiotics: a model for synthetic biology to accelerate the evolution of secondary metabolite biosynthetic pathways.

    Science.gov (United States)

    Baltz, Richard H

    2014-10-17

    Nonribosomal peptide synthetases (NRPSs) are giant multi-enzymes that carry out sequencial assembly line couplings of amino acids to generate linear or cyclic peptides. NRPSs are composed of repeating enzyme domains with modular organization to activate and couple specific amino acids in a particular order. From a synthetic biology perspective, they can be considered as peptide assembly machines composed of devices to couple fatty acids to l-amino acids, l-amino acids to l-amino acids, and d-amino acids to l-amino acids. The coupling devices are composed of specific parts that contain two or more enzyme domains that can be exchanged combinatorially to generate novel peptide assembly machines to produce novel peptides. The potent lipopeptide antibiotics daptomycin and A54145E have identical cyclic depsipeptide ring structures and stereochemistry but have divergent amino acid sequences. As their biosynthetic gene clusters are derived from an ancient ancestral lipopetide pathway, these lipopeptides provided an attractive model to develop combinatorial biosynthesis to generate antibiotics superior to daptomycin. These studies on combinatorial biosynthesis have helped generate guidelines for the successful assembly of NRPS parts and devices that can be used to generate novel lipopeptide structures and have established a basis for future synthetic biology studies to further develop combinatorial biosynthesis as a robust approach to natural product drug discovery.

  15. Physics of new methods of charged particle acceleration collective effects in dense charged particle ensembles

    CERN Document Server

    Bonch-Osmolovsky, A G

    1994-01-01

    This volume discusses the theory of new methods of charged particle acceleration and its physical and mathematical descriptions. It examines some collective effects in dense charged particle ensembles, and traces the history of the development of the field of accelerator physics.

  16. A follow-up study of women in the synthetic rubber industry: study methods.

    Science.gov (United States)

    Sathiakumar, Nalini; Delzell, Elizabeth

    2007-03-20

    Concerns about the possible toxic effects of workplace exposures in the synthetic rubber industry have centered on 1,3-butadiene (BD), styrene and dimethyldithiocarbamate (DMDTC). Our previous mortality studies of over 17,000 male synthetic rubber workers found an excess of leukemia that may be due to BD or BD plus other chemicals. Experimental studies have shown that BD produces mammary tumors in female mice and rats and ovarian tumors in female mice. This paper presents the methods of a follow-up study that evaluates the mortality experience of women employed in the North American synthetic rubber industry. Women employed for at least 1 day at any of eight North American styrene-butadiene rubber plants were followed up from 1943 to 2002. Identifying and work history information were obtained from personnel records. Estimated quantitative exposure to BD, styrene and DMDTC, developed for our previous study of men, were used in this study. External analyses use the standardized mortality ratios (SMRs) to compare the cohort's cause-specific mortality rates to the rates of the female general population of the states or the province where the plants are located. Internal analyses use the Poisson regression and Cox proportional hazards models to examine specific cancer mortality rates in relation to BD, styrene and DMDTC exposure, by comparing an exposed cohort subgroup with the rate of unexposed cohort members.

  17. Estimating the Impacts of Local Policy Innovation: The Synthetic Control Method Applied to Tropical Deforestation

    Science.gov (United States)

    Sills, Erin O.; Herrera, Diego; Kirkpatrick, A. Justin; Brandão, Amintas; Dickson, Rebecca; Hall, Simon; Pattanayak, Subhrendu; Shoch, David; Vedoveto, Mariana; Young, Luisa; Pfaff, Alexander

    2015-01-01

    Quasi-experimental methods increasingly are used to evaluate the impacts of conservation interventions by generating credible estimates of counterfactual baselines. These methods generally require large samples for statistical comparisons, presenting a challenge for evaluating innovative policies implemented within a few pioneering jurisdictions. Single jurisdictions often are studied using comparative methods, which rely on analysts’ selection of best case comparisons. The synthetic control method (SCM) offers one systematic and transparent way to select cases for comparison, from a sizeable pool, by focusing upon similarity in outcomes before the intervention. We explain SCM, then apply it to one local initiative to limit deforestation in the Brazilian Amazon. The municipality of Paragominas launched a multi-pronged local initiative in 2008 to maintain low deforestation while restoring economic production. This was a response to having been placed, due to high deforestation, on a federal “blacklist” that increased enforcement of forest regulations and restricted access to credit and output markets. The local initiative included mapping and monitoring of rural land plus promotion of economic alternatives compatible with low deforestation. The key motivation for the program may have been to reduce the costs of blacklisting. However its stated purpose was to limit deforestation, and thus we apply SCM to estimate what deforestation would have been in a (counterfactual) scenario of no local initiative. We obtain a plausible estimate, in that deforestation patterns before the intervention were similar in Paragominas and the synthetic control, which suggests that after several years, the initiative did lower deforestation (significantly below the synthetic control in 2012). This demonstrates that SCM can yield helpful land-use counterfactuals for single units, with opportunities to integrate local and expert knowledge and to test innovations and permutations on

  18. Estimating the Impacts of Local Policy Innovation: The Synthetic Control Method Applied to Tropical Deforestation.

    Science.gov (United States)

    Sills, Erin O; Herrera, Diego; Kirkpatrick, A Justin; Brandão, Amintas; Dickson, Rebecca; Hall, Simon; Pattanayak, Subhrendu; Shoch, David; Vedoveto, Mariana; Young, Luisa; Pfaff, Alexander

    2015-01-01

    Quasi-experimental methods increasingly are used to evaluate the impacts of conservation interventions by generating credible estimates of counterfactual baselines. These methods generally require large samples for statistical comparisons, presenting a challenge for evaluating innovative policies implemented within a few pioneering jurisdictions. Single jurisdictions often are studied using comparative methods, which rely on analysts' selection of best case comparisons. The synthetic control method (SCM) offers one systematic and transparent way to select cases for comparison, from a sizeable pool, by focusing upon similarity in outcomes before the intervention. We explain SCM, then apply it to one local initiative to limit deforestation in the Brazilian Amazon. The municipality of Paragominas launched a multi-pronged local initiative in 2008 to maintain low deforestation while restoring economic production. This was a response to having been placed, due to high deforestation, on a federal "blacklist" that increased enforcement of forest regulations and restricted access to credit and output markets. The local initiative included mapping and monitoring of rural land plus promotion of economic alternatives compatible with low deforestation. The key motivation for the program may have been to reduce the costs of blacklisting. However its stated purpose was to limit deforestation, and thus we apply SCM to estimate what deforestation would have been in a (counterfactual) scenario of no local initiative. We obtain a plausible estimate, in that deforestation patterns before the intervention were similar in Paragominas and the synthetic control, which suggests that after several years, the initiative did lower deforestation (significantly below the synthetic control in 2012). This demonstrates that SCM can yield helpful land-use counterfactuals for single units, with opportunities to integrate local and expert knowledge and to test innovations and permutations on policies

  19. A method for measuring the high voltage of a low energy Van de Graaff accelerator

    Science.gov (United States)

    Andrade, E.; Zironi, E. P.

    1988-12-01

    A simple method for measuring the operating high voltage of a small positive ion Van de Graaff accelerator was developed. It is based on the determination of the end-point energy obtained from the X-ray radiation spectra. The accuracy of the proposed method is better than 1%. Most of these accelerators have an associated magnetic beam analyzer and/or generator voltmeter gauges that require calibration. The proposed method can be used to calibrate these instruments.

  20. Efficient narrowband interference suppression method for synthetic aperture radar-based on variational mode decomposition

    Science.gov (United States)

    Lu, Xingyu; Su, Weimin; Yang, Jianchao; Gu, Hong

    2017-10-01

    The narrowband interference (NBI) can degrade the synthetic aperture radar (SAR) imaging quality severely. This paper proposes an NBI mitigation method using the variational mode decomposition (VMD). The coarse estimation of NBI is obtained by decomposing the real part and imaginary part of the complex-valued raw echoes into a number of modes by VMD independently. Next, modes that correspond to NBI are refined by the mask technique in the frequency domain. Then the interference is mitigated by subtracting the refined estimated NBI components from the echoes, and a well-focused SAR image is obtained by conventional imaging schemes. The proposed method outperforms other time-varying NBI mitigation methods with smaller effective data loss and less impact on the focusing performance of images. Results of simulated and measured data prove the validity of the proposed method.

  1. A method to evaluate residual phase error for polar formatted synthetic aperture radar systems

    Science.gov (United States)

    Musgrove, Cameron; Naething, Richard

    2013-05-01

    Synthetic aperture radar systems that use the polar format algorithm are subject to a focused scene size limit inherent to the polar format algorithm. The classic focused scene size limit is determined from the dominant residual range phase error term. Given the many sources of phase error in a synthetic aperture radar, a system designer is interested in how much phase error results from the assumptions made with the polar format algorithm. Autofocus algorithms have limits to the amount and type of phase error that can be corrected. Current methods correct only one or a few terms of the residual phase error. A system designer needs to be able to evaluate the contribution of the residual or uncorrected phase error terms to determine the new focused scene size limit. This paper describes a method to estimate the complete residual phase error, not just one or a few of the dominant residual terms. This method is demonstrated with polar format image formation, but is equally applicable to other image formation algorithms. A benefit for the system designer is that additional correction terms can be added or deleted from the analysis as necessary to evaluate the resulting effect upon image quality.

  2. QuickLib, a method for building fully synthetic plasmid libraries by seamless cloning of degenerate oligonucleotides

    Science.gov (United States)

    Galka, Pierre; Jamez, Elisabeth; Joachim, Gilles

    2017-01-01

    Incorporation of synthetic degenerate oligonucleotides into plasmids for building highly diverse genetic libraries requires efficient and quantitative DNA manipulation. We present a fast and seamless method for generating libraries of PCR-synthesized plasmids designed with a degenerate sequence and short overlapping ends. Our method called QuickLib should find many applications in synthetic biology; as an example, we easily prepared genetic libraries of Escherichia coli expressing billions of different backbone cyclic peptides. PMID:28406948

  3. The measurement of the fluence rate of accelerator fusion neutrons by using the associated particle method

    International Nuclear Information System (INIS)

    Wang Dalun; Li Yijun; Jiang Li

    1998-11-01

    The associated particle method is normally used to measure the fluence rate of accelerator fusion neutron. The principle, set-up and technical points are standardized. The measurement error is up to 1%∼1.5%

  4. Limitations and Strengths of the Fourier Transform Method to Detect Accelerating Targets

    National Research Council Canada - National Science Library

    Thayaparan, Thayananthan

    2000-01-01

    .... In using a Pulse Doppler Radar to detect a non-accelerating target in additive white Gaussian noise and to estimate its radial velocity, the Fourier method provides an output signal-to-noise ratio (SNR...

  5. The Lozanov Method for Accelerating the Learning of Foreign Languages.

    Science.gov (United States)

    Stanton, H. E.

    1978-01-01

    Discusses the Lozanov Method of teaching foreign languages developed by Lozanov in Bulgaria. This method (also known as Suggestopedia) uses various techniques such as physical relaxation exercises, mental concentration, classical music, and ego-enhancing suggestions. (CFM)

  6. A new method of measuring gravitational acceleration in an undergraduate laboratory program

    Science.gov (United States)

    Wang, Qiaochu; Wang, Chang; Xiao, Yunhuan; Schulte, Jurgen; Shi, Qingfan

    2018-01-01

    This paper presents a high accuracy method to measure gravitational acceleration in an undergraduate laboratory program. The experiment is based on water in a cylindrical vessel rotating about its vertical axis at a constant speed. The water surface forms a paraboloid whose focal length is related to rotational period and gravitational acceleration. This experimental setup avoids classical source errors in determining the local value of gravitational acceleration, so prevalent in the common simple pendulum and inclined plane experiments. The presented method combines multiple physics concepts such as kinematics, classical mechanics and geometric optics, offering the opportunity for lateral as well as project-based learning.

  7. Computer control of large accelerators design concepts and methods

    Energy Technology Data Exchange (ETDEWEB)

    Beck, F.; Gormley, M.

    1984-05-01

    Unlike most of the specialities treated in this volume, control system design is still an art, not a science. These lectures are an attempt to produce a primer for prospective practitioners of this art. A large modern accelerator requires a comprehensive control system for commissioning, machine studies and day-to-day operation. Faced with the requirement to design a control system for such a machine, the control system architect has a bewildering array of technical devices and techniques at his disposal, and it is our aim in the following chapters to lead him through the characteristics of the problems he will have to face and the practical alternatives available for solving them. We emphasize good system architecture using commercially available hardware and software components, but in addition we discuss the actual control strategies which are to be implemented since it is at the point of deciding what facilities shall be available that the complexity of the control system and its cost are implicitly decided. 19 references.

  8. Computer control of large accelerators design concepts and methods

    International Nuclear Information System (INIS)

    Beck, F.; Gormley, M.

    1984-05-01

    Unlike most of the specialities treated in this volume, control system design is still an art, not a science. These lectures are an attempt to produce a primer for prospective practitioners of this art. A large modern accelerator requires a comprehensive control system for commissioning, machine studies and day-to-day operation. Faced with the requirement to design a control system for such a machine, the control system architect has a bewildering array of technical devices and techniques at his disposal, and it is our aim in the following chapters to lead him through the characteristics of the problems he will have to face and the practical alternatives available for solving them. We emphasize good system architecture using commercially available hardware and software components, but in addition we discuss the actual control strategies which are to be implemented since it is at the point of deciding what facilities shall be available that the complexity of the control system and its cost are implicitly decided. 19 references

  9. Methods of Phase and Power Control in Magnetron Transmitters for Superconducting Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Kazadevich, G. [MUONS Inc., Batavia; Johnson, R. [MUONS Inc., Batavia; Neubauer, M. [MUONS Inc., Batavia; Lebedev, V. [Fermilab; Schappert, W. [Fermilab; Yakovlev, V. [Fermilab

    2017-05-01

    Various methods of phase and power control in magnetron RF sources of superconducting accelerators intended for ADS-class projects were recently developed and studied with conventional 2.45 GHz, 1 kW, CW magnetrons operating in pulsed and CW regimes. Magnetron transmitters excited by a resonant (injection-locking) phasemodulated signal can provide phase and power control with the rates required for precise stabilization of phase and amplitude of the accelerating field in Superconducting RF (SRF) cavities of the intensity-frontier accelerators. An innovative technique that can significantly increase the magnetron transmitter efficiency at the widerange power control required for superconducting accelerators was developed and verified with the 2.45 GHz magnetrons operating in CW and pulsed regimes. High efficiency magnetron transmitters of this type can significantly reduce the capital and operation costs of the ADSclass accelerator projects.

  10. Convergence Property of Response Matrix Method for Various Finite-Difference Formulations Used in the Nonlinear Acceleration Method

    International Nuclear Information System (INIS)

    Yamamoto, Akio

    2005-01-01

    Convergence properties were investigated for the response matrix method with various finite-difference formulations that can be utilized in the nonlinear acceleration method. The nonlinear acceleration method is commonly used for the diffusion calculation with the advanced nodal method or the transport calculation with the method of characteristics. Efficiency of the nonlinear acceleration method depends on convergences on two different levels, i.e., those of the finite-difference calculation and the correction factor. This paper focuses on the former topic, i.e., the convergence property of finite-difference calculations using the response matrix method. Though various finite-difference formulations can be used in the nonlinear acceleration method, systematic analysis of the convergence property for the finite-difference calculation has not been carried out so far. The spectral radius of iteration matrixes was estimated for the various finite-difference calculations assuming the response matrix method with the red-black sweep. From the calculation results, numerical stability of the various finite-difference formulations was clarified, and a favorable form of the finite-difference formulation for the nonlinear iteration was recommended. The result of this paper will be useful for implementation of the nonlinear acceleration scheme with the response matrix method

  11. Planetary method to measure the neutrons spectrum in lineal accelerators of medical use

    International Nuclear Information System (INIS)

    Vega C, H. R.; Benites R, J. L.

    2014-08-01

    A novel procedure to measure the neutrons spectrum originated in a lineal accelerator of medical use has been developed. The method uses a passive spectrometer of Bonner spheres. The main advantage of the method is that only requires of a single shot of the accelerator. When this is used around a lineal accelerator is necessary to operate it under the same conditions so many times like the spheres that contain the spectrometer, activity that consumes enough time. The developed procedure consists on situating all the spheres of the spectrometer at the same time and to realize the reading making a single shot. With this method the photo neutrons spectrum produced by a lineal accelerator Varian ix of 15 MV to 100 cm of the isocenter was determined, with the spectrum is determined the total flow and the ambient dose equivalent. (Author)

  12. An Adaptive Laboratory Evolution Method to Accelerate Autotrophic Metabolism

    DEFF Research Database (Denmark)

    Zhang, Tian; Tremblay, Pier-Luc

    2018-01-01

    Adaptive laboratory evolution (ALE) is an approach enabling the development of novel characteristics in microbial strains via the application of a constant selection pressure. This method is also an efficient tool to acquire insights on molecular mechanisms responsible for specific phenotypes. AL...... autotrophically and reducing CO2 into acetate more efficiently. Strains developed via this ALE method were also used to gain knowledge on the autotrophic metabolism of S. ovata as well as other acetogenic bacteria....

  13. Electrochemical growth of synthetic melanin thin films by constant potential methods

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Gyun; Nam, Hye Jin; Ahn, Hyeon Ju [Department of Chemistry, School of Chemical Materials Science, Institute of Basic Sciences, Sungkyunkwan Advanced Institute of NanoTechnology (SAINT), Sungkyunkwan University, Chunchun-dong, Gyunggi-do, Suwon 440-746 (Korea, Republic of); Jung, Duk-Young, E-mail: dyjung@skku.ed [Department of Chemistry, School of Chemical Materials Science, Institute of Basic Sciences, Sungkyunkwan Advanced Institute of NanoTechnology (SAINT), Sungkyunkwan University, Chunchun-dong, Gyunggi-do, Suwon 440-746 (Korea, Republic of)

    2011-02-28

    Polymerized melanin thin films were electrochemically synthesized in a 5,6-dihydroxyindole precursor solution on indium tin oxide (ITO) substrates using the cyclic voltammetry and constant potential methods. Tris(hydroxymethyl)aminomethane (THAM) and phosphate buffer solutions were applied to prepare the films that were well deposited to the ITO substrates. The films that were synthesized in the THAM buffer solution exhibited a faster growth rate and better adhesion to the ITO electrodes than the films in the phosphate buffer. The film thickness linearly increased at the growth rate of 0.8 nm/s as the deposition time and number of cycles increased. Two electrochemical conditions produced similar thicknesses as well as physical properties in each buffer solution. However, the constant potential method demonstrated that this provides the synthetic advantages of faster deposition and less consumption of electric charge compared to the cyclic voltammetry route.

  14. A GPU-accelerated implicit meshless method for compressible flows

    Science.gov (United States)

    Zhang, Jia-Le; Ma, Zhi-Hua; Chen, Hong-Quan; Cao, Cheng

    2018-05-01

    This paper develops a recently proposed GPU based two-dimensional explicit meshless method (Ma et al., 2014) by devising and implementing an efficient parallel LU-SGS implicit algorithm to further improve the computational efficiency. The capability of the original 2D meshless code is extended to deal with 3D complex compressible flow problems. To resolve the inherent data dependency of the standard LU-SGS method, which causes thread-racing conditions destabilizing numerical computation, a generic rainbow coloring method is presented and applied to organize the computational points into different groups by painting neighboring points with different colors. The original LU-SGS method is modified and parallelized accordingly to perform calculations in a color-by-color manner. The CUDA Fortran programming model is employed to develop the key kernel functions to apply boundary conditions, calculate time steps, evaluate residuals as well as advance and update the solution in the temporal space. A series of two- and three-dimensional test cases including compressible flows over single- and multi-element airfoils and a M6 wing are carried out to verify the developed code. The obtained solutions agree well with experimental data and other computational results reported in the literature. Detailed analysis on the performance of the developed code reveals that the developed CPU based implicit meshless method is at least four to eight times faster than its explicit counterpart. The computational efficiency of the implicit method could be further improved by ten to fifteen times on the GPU.

  15. Accelerated in vitro release testing method for naltrexone loaded PLGA microspheres.

    Science.gov (United States)

    Andhariya, Janki V; Choi, Stephanie; Wang, Yan; Zou, Yuan; Burgess, Diane J; Shen, Jie

    2017-03-30

    The objective of the present study was to develop a discriminatory and reproducible accelerated release testing method for naltrexone loaded parenteral polymeric microspheres. The commercially available naltrexone microsphere product (Vivitrol ® ) was used as the testing formulation in the in vitro release method development, and both sample-and-separate and USP apparatus 4 methods were investigated. Following an in vitro drug stability study, frequent media replacement and addition of anti-oxidant in the release medium were used to prevent degradation of naltrexone during release testing at "real-time" (37°C) and "accelerated" (45°C), respectively. The USP apparatus 4 method was more reproducible than the sample-and-separate method. In addition, the accelerated release profile obtained using USP apparatus 4 had a shortened release duration (within seven days), and good correlation with the "real-time" release profile. Lastly, the discriminatory ability of the developed accelerated release method was assessed using compositionally equivalent naltrexone microspheres with different release characteristics. The developed accelerated USP apparatus 4 release method was able to detect differences in the release characteristics of the prepared naltrexone microspheres. Moreover, a linear correlation was observed between the "real-time" and accelerated release profiles of all the formulations investigated, suggesting that the release mechanism(s) may be similar under both conditions. These results indicate that the developed accelerated USP apparatus 4 method has the potential to be an appropriate fast quality control tool for long-acting naltrexone PLGA microspheres. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Engineering Bacteria to Search for Specific Concentrations of Molecules by a Systematic Synthetic Biology Design Method.

    Science.gov (United States)

    Tien, Shin-Ming; Hsu, Chih-Yuan; Chen, Bor-Sen

    2016-01-01

    Bacteria navigate environments full of various chemicals to seek favorable places for survival by controlling the flagella's rotation using a complicated signal transduction pathway. By influencing the pathway, bacteria can be engineered to search for specific molecules, which has great potential for application to biomedicine and bioremediation. In this study, genetic circuits were constructed to make bacteria search for a specific molecule at particular concentrations in their environment through a synthetic biology method. In addition, by replacing the "brake component" in the synthetic circuit with some specific sensitivities, the bacteria can be engineered to locate areas containing specific concentrations of the molecule. Measured by the swarm assay qualitatively and microfluidic techniques quantitatively, the characteristics of each "brake component" were identified and represented by a mathematical model. Furthermore, we established another mathematical model to anticipate the characteristics of the "brake component". Based on this model, an abundant component library can be established to provide adequate component selection for different searching conditions without identifying all components individually. Finally, a systematic design procedure was proposed. Following this systematic procedure, one can design a genetic circuit for bacteria to rapidly search for and locate different concentrations of particular molecules by selecting the most adequate "brake component" in the library. Moreover, following simple procedures, one can also establish an exclusive component library suitable for other cultivated environments, promoter systems, or bacterial strains.

  17. Engineering Bacteria to Search for Specific Concentrations of Molecules by a Systematic Synthetic Biology Design Method.

    Directory of Open Access Journals (Sweden)

    Shin-Ming Tien

    Full Text Available Bacteria navigate environments full of various chemicals to seek favorable places for survival by controlling the flagella's rotation using a complicated signal transduction pathway. By influencing the pathway, bacteria can be engineered to search for specific molecules, which has great potential for application to biomedicine and bioremediation. In this study, genetic circuits were constructed to make bacteria search for a specific molecule at particular concentrations in their environment through a synthetic biology method. In addition, by replacing the "brake component" in the synthetic circuit with some specific sensitivities, the bacteria can be engineered to locate areas containing specific concentrations of the molecule. Measured by the swarm assay qualitatively and microfluidic techniques quantitatively, the characteristics of each "brake component" were identified and represented by a mathematical model. Furthermore, we established another mathematical model to anticipate the characteristics of the "brake component". Based on this model, an abundant component library can be established to provide adequate component selection for different searching conditions without identifying all components individually. Finally, a systematic design procedure was proposed. Following this systematic procedure, one can design a genetic circuit for bacteria to rapidly search for and locate different concentrations of particular molecules by selecting the most adequate "brake component" in the library. Moreover, following simple procedures, one can also establish an exclusive component library suitable for other cultivated environments, promoter systems, or bacterial strains.

  18. Advanced FDTD methods parallelization, acceleration, and engineering applications

    CERN Document Server

    Yu, Wenhua

    2011-01-01

    The finite-difference time-domain (FDTD) method has revolutionized antenna design and electromagnetics engineering. Here's a cutting-edge book that focuses on the performance optimization and engineering applications of FDTD simulation systems. Covering the latest developments in this area, this unique resource offer you expert advice on the FDTD method, hardware platforms, and network systems. Moreover the book offers guidance in distinguishing between the many different electromagnetics software packages on the market today. You also find a complete chapter dedicated to large multi-scale pro

  19. Stability analysis of CMFD acceleration for the wavelet expansion method of neutron transport equation

    International Nuclear Information System (INIS)

    Zheng Youqi; Wu Hongchun; Cao Liangzhi

    2013-01-01

    This paper describes the stability analysis for the coarse mesh finite difference (CMFD) acceleration used in the wavelet expansion method. The nonlinear CMFD acceleration scheme is transformed by linearization and the Fourier ansatz is introduced into the linearized formulae. The spectral radius is defined as the stability criterion, which is the least upper bound (LUB) of the largest eigenvalue of Fourier analysis matrix. The stability analysis considers the effect of mesh size (spectral length), coarse mesh division and scattering ratio. The results show that for the wavelet expansion method, the CMFD acceleration is conditionally stable. The small size of fine mesh brings stability and fast convergent. With the increase of the mesh size, the stability becomes worse. The scattering ratio does not impact the stability obviously. It makes the CMFD acceleration highly efficient in the strong scattering case. The results of Fourier analysis are verified by the numerical tests based on a homogeneous slab problem.

  20. An accelerated test method of luminous flux depreciation for LED luminaires and lamps

    International Nuclear Information System (INIS)

    Qian, C.; Fan, X.J.; Fan, J.J.; Yuan, C.A.; Zhang, G.Q.

    2016-01-01

    Light Emitting Diode (LED) luminaires and lamps are energy-saving and environmental friendly alternatives to traditional lighting products. However, current luminous flux depreciation test at luminaire and lamp level requires a minimum of 6000 h testing, which is even longer than the product development cycle time. This paper develops an accelerated test method for luminous flux depreciation to reduce the test time within 2000 h at an elevated temperature. The method is based on lumen maintenance boundary curve, obtained from a collection of LED source lumen depreciation data, known as LM-80 data. The exponential decay model and Arrhenius acceleration relationship are used to determine the new threshold of lumen maintenance and acceleration factor. The proposed method has been verified by a number of simulation studies and experimental data for a wide range of LED luminaire and lamp types from both internal and external experiments. The qualification results obtained by the accelerated test method agree well with traditional 6000 h tests. - Highlights: • We develop an accelerated test method for LED luminaires and lamps. • The method is proposed based on a “Boundary Curve” concept. • The parameters of the boundary curve are extracted from LM-80 test reports. • Qualification results from the proposed method agree with ES requirements.

  1. On accelerated flow of MHD powell-eyring fluid via homotopy analysis method

    Science.gov (United States)

    Salah, Faisal; Viswanathan, K. K.; Aziz, Zainal Abdul

    2017-09-01

    The aim of this article is to obtain the approximate analytical solution for incompressible magnetohydrodynamic (MHD) flow for Powell-Eyring fluid induced by an accelerated plate. Both constant and variable accelerated cases are investigated. Approximate analytical solution in each case is obtained by using the Homotopy Analysis Method (HAM). The resulting nonlinear analysis is carried out to generate the series solution. Finally, Graphical outcomes of different values of the material constants parameters on the velocity flow field are discussed and analyzed.

  2. Constraint methods that accelerate free-energy simulations of biomolecules

    International Nuclear Information System (INIS)

    Perez, Alberto; MacCallum, Justin L.; Coutsias, Evangelos A.; Dill, Ken A.

    2015-01-01

    Atomistic molecular dynamics simulations of biomolecules are critical for generating narratives about biological mechanisms. The power of atomistic simulations is that these are physics-based methods that satisfy Boltzmann’s law, so they can be used to compute populations, dynamics, and mechanisms. But physical simulations are computationally intensive and do not scale well to the sizes of many important biomolecules. One way to speed up physical simulations is by coarse-graining the potential function. Another way is to harness structural knowledge, often by imposing spring-like restraints. But harnessing external knowledge in physical simulations is problematic because knowledge, data, or hunches have errors, noise, and combinatoric uncertainties. Here, we review recent principled methods for imposing restraints to speed up physics-based molecular simulations that promise to scale to larger biomolecules and motions

  3. Free Trade Zone of Manaus: An Impact Evaluation using the Synthetic Control Method

    Directory of Open Access Journals (Sweden)

    Vítor Possebom

    Full Text Available I apply the synthetic control method to Brazilian city-level data during the twentieth century in order to evaluate the economic impact of the Free Trade Zone of Manaus (FTZM. I find that this enterprise zone had significantly positive effects on real GDP per capita and Services Total Production per capita, but it also had significantly negative effects on Agriculture Total Production per capita. My results suggest that this subsidy policy achieved its goal of promoting regional economic growth at the cost of creating mis-allocation of resources among economic sectors. They also reject the view that an industrialization policy will benefit all economic sectors due to positive spill-overs from the manufacturing sector that are strong enough to compensate for the negative effect of the mis-allocation of resources.

  4. GPU Acceleration of Particle-In-Cell Methods

    Science.gov (United States)

    Cowan, Benjamin; Averkin, Sergey; Cary, John; Leddy, Jarrod; Sides, Scott; Werner, Gregory

    2017-10-01

    Graphics processing units (GPUs) have become key components in many supercomputing systems, as they can provide more computations relative to their cost and power consumption than conventional processors. However, to take full advantage of this capability, they require a strict programming model which involves single-instruction multiple-data execution as well as significant constraints on memory access. To bring the full power of GPUs to bear on plasma physics problems, we must adapt the computational methods to this new programming model. We have developed a GPU implementation of the particle-in-cell (PIC) method, one of the mainstays of plasma physics simulation. This framework is highly general and enables advanced PIC features such as high order particles and absorbing boundary conditions. The main elements of the PIC loop, including field interpolation and particle deposition, are designed to optimize memory access. We describe recent progress in these algorithms, including arbitrary grid types and multiple GPUs per node. Work supported by DARPA Contract No. W31P4Q-16-C-0009.

  5. An Organocatalyzed and Ultrasound Accelerated Expeditious Synthetic Route to 1,5-Benzodiazepines under Solvent-Free Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, Pravin V.; Shingate, Bapurao B.; Shingare, Murlidhar S. [Babasaheb Ambedkar Marathwada University, Aurngabad (India)

    2011-04-15

    In the present work, successful implementation of ultrasound irradiations for the rapid synthesis of 1,5- benzodiazepine derivatives under solvent-free conditions is demonstrated. Use of a novel catalyst i.e. camphor sulphonic acid in combination with ultrasound technique is reported for the first time. Comparative study for the synthesis of 1,5-benzodiazepines using conventional as well as ultrasonication method is discussed.

  6. Apparatus and method for phosphate-accelerated bioremediation

    Science.gov (United States)

    Looney, Brian B.; Pfiffner, Susan M.; Phelps, Tommy J.; Lombard, Kenneth H.; Hazen, Terry C.; Borthen, James W.

    1998-01-01

    An apparatus and method for supplying a vapor-phase nutrient to contaminated soil for in situ bioremediation. The apparatus includes a housing adapted for containing a quantity of the liquid nutrient, a conduit in communication with the interior of the housing, means for causing a gas to flow through the conduit, and means for contacting the gas with the liquid so that a portion thereof evaporates and mixes with the gas. The mixture of gas and nutrient vapor is delivered to the contaminated site via a system of injection and extraction wells configured to the site and provides for the use of a passive delivery system. The mixture has a partial pressure of vaporized nutrient that is no greater than the vapor pressure of the liquid. If desired, the nutrient and/or the gas may be heated to increase the vapor pressure and the nutrient concentration of the mixture. Preferably, the nutrient is a volatile, substantially nontoxic and nonflammable organic phosphate that is a liquid at environmental temperatures, such as triethyl phosphate or tributyl phosphate.

  7. The two-dimensional Gaussian beam synthetic method: Testing and application

    Science.gov (United States)

    Nowack, R.; Aki, K.

    1984-09-01

    The Gaussian beam method of Červený et al. (1982) is an asymptotic method for the computation of wave fields in inhomogeneous media. The method consists of tracing rays and then solving the wave equation in "ray-centered coordinates." The parabolic approximation is applied to find the asymptotic local solution in the neighborhod of each ray. The approximate global solution for a given source is then constructed by a superposition of Gaussian beams along nearby rays. The Gaussian beam method is tested in a two-dimensional inhomogeneous medium using two approaches. One is the application of the reciprocal theorem for Green's functions in an arbitrarily heterogeneous medium. The discrepancy between synthetic seismograms for reciprocal cases is considered as a measure of the error. The other approach is to apply Gaussian beam synthesis to cases for which solutions are known by other approximate methods. This includes the soft basin problem that has been studied by finite difference, finite element, discrete wavenumber, and glorified optics. We found that the results of these tests were in general satisfactory. We have used the Gaussian beam method for two applications. First, the method is used to study volcanic earthquakes at Mount Saint Helens. The observed large differences in amplitude and arrival time between a station inside the crater and stations on the flanks can be explained by the combined effects of an anomalous velocity structure and a shallow focal depth. The method is also applied to scattering of teleseismic P waves by a lithosphere with randomly fluctuating velocities.

  8. Predictive Simulation and Design of Materials by Quasicontinuum and Accelerated Dynamics Methods

    Energy Technology Data Exchange (ETDEWEB)

    Luskin, Mitchell [University of Minnesota; James, Richard; Tadmor, Ellad

    2014-03-30

    This project developed the hyper-QC multiscale method to make possible the computation of previously inaccessible space and time scales for materials with thermally activated defects. The hyper-QC method combines the spatial coarse-graining feature of a finite temperature extension of the quasicontinuum (QC) method (aka “hot-QC”) with the accelerated dynamics feature of hyperdynamics. The hyper-QC method was developed, optimized, and tested from a rigorous mathematical foundation.

  9. A flexible nonlinear diffusion acceleration method for the SN transport equations discretized with discontinuous finite elements

    Science.gov (United States)

    Schunert, Sebastian; Wang, Yaqi; Gleicher, Frederick; Ortensi, Javier; Baker, Benjamin; Laboure, Vincent; Wang, Congjian; DeHart, Mark; Martineau, Richard

    2017-06-01

    This work presents a flexible nonlinear diffusion acceleration (NDA) method that discretizes both the SN transport equation and the diffusion equation using the discontinuous finite element method (DFEM). The method is flexible in that the diffusion equation can be discretized on a coarser mesh with the only restriction that it is nested within the transport mesh and the FEM shape function orders of the two equations can be different. The consistency of the transport and diffusion solutions at convergence is defined by using a projection operator mapping the transport into the diffusion FEM space. The diffusion weak form is based on the modified incomplete interior penalty (MIP) diffusion DFEM discretization that is extended by volumetric drift, interior face, and boundary closure terms. In contrast to commonly used coarse mesh finite difference (CMFD) methods, the presented NDA method uses a full FEM discretized diffusion equation for acceleration. Suitable projection and prolongation operators arise naturally from the FEM framework. Via Fourier analysis and numerical experiments for a one-group, fixed source problem the following properties of the NDA method are established for structured quadrilateral meshes: (1) the presented method is unconditionally stable and effective in the presence of mild material heterogeneities if the same mesh and identical shape functions either of the bilinear or biquadratic type are used, (2) the NDA method remains unconditionally stable in the presence of strong heterogeneities, (3) the NDA method with bilinear elements extends the range of effectiveness and stability by a factor of two when compared to CMFD if a coarser diffusion mesh is selected. In addition, the method is tested for solving the C5G7 multigroup, eigenvalue problem using coarse and fine mesh acceleration. While NDA does not offer an advantage over CMFD for fine mesh acceleration, it reduces the iteration count required for convergence by almost a factor of two in

  10. Bismuth-ceramic nanocomposites through ball milling and liquid crystal synthetic methods

    Science.gov (United States)

    Dellinger, Timothy Michael

    Three methods were developed for the synthesis of bismuth-ceramic nanocomposites, which are of interest due to possible use as thermoelectric materials. In the first synthetic method, high energy ball milling of bismuth metal with either MgO or SiO2 was found to produce nanostructured bismuth dispersed on a ceramic material. The morphology of the resulting bismuth depended on its wetting behavior with respect to the ceramic: the metal wet the MgO, but did not wet on the SiO2. Differential Scanning Calorimetry measurements on these composites revealed unusual thermal stability, with nanostructure retained after multiple cycles of heating and cooling through the metal's melting point. The second synthesis methodology was based on the use of lyotropic liquid crystals. These mixtures of water and amphiphilic molecules self-assemble to form periodic structures with nanometer-scale hydrophilic and hydrophobic domains. A novel shear mixing methodology was developed for bringing together reactants which were added to the liquid crystals as dissolved salts. The liquid crystals served to mediate synthesis by acting as nanoreactors to confine chemical reactions within the nanoscale domains of the mesophase, and resulted in the production of nanoparticles. By synthesizing lead sulfide (PbS) and bismuth (Bi) particles as proof-of-concept, it was shown that nanoparticle size could be controlled by controlling the dimensionality of the nanoreactors through control of the liquid crystalline phase. Particle size was shown to decrease upon going from three-dimensionally percolating nanoreactors, to two dimensional sheet-like nanoreactors, to one dimensional rod-like nanoreactors. Additionally, particle size could be controlled by varying the precursor salt concentration. Since the nanoparticles did not agglomerate in the liquid crystal immediately after synthesis, bismuth-ceramic nanocomposites could be prepared by synthesizing Bi nanoparticles and mixing in SiO2 particles which

  11. Three dimensional finite element methods: Their role in the design of DC accelerator systems

    Energy Technology Data Exchange (ETDEWEB)

    Podaru, Nicolae C.; Gottdang, A.; Mous, D. J. W. [High Voltage Engineering Europa B.V., P.O. Box 99, 3800 AB, Amersfoort (Netherlands)

    2013-04-19

    High Voltage Engineering has designed, built and tested a 2 MV dual irradiation system that will be applied for radiation damage studies and ion beam material modification. The system consists of two independent accelerators which support simultaneous proton and electron irradiation (energy range 100 keV - 2 MeV) of target sizes of up to 300 Multiplication-Sign 300 mm{sup 2}. Three dimensional finite element methods were used in the design of various parts of the system. The electrostatic solver was used to quantify essential parameters of the solid-state power supply generating the DC high voltage. The magnetostatic solver and ray tracing were used to optimize the electron/ion beam transport. Close agreement between design and measurements of the accelerator characteristics as well as beam performance indicate the usefulness of three dimensional finite element methods during accelerator system design.

  12. An Optimal DEM Reconstruction Method for Linear Array Synthetic Aperture Radar Based on Variational Model

    Directory of Open Access Journals (Sweden)

    Shi Jun

    2015-02-01

    Full Text Available Downward-looking Linear Array Synthetic Aperture Radar (LASAR has many potential applications in the topographic mapping, disaster monitoring and reconnaissance applications, especially in the mountainous area. However, limited by the sizes of platforms, its resolution in the linear array direction is always far lower than those in the range and azimuth directions. This disadvantage leads to the blurring of Three-Dimensional (3D images in the linear array direction, and restricts the application of LASAR. To date, the research on 3D SAR image enhancement has focused on the sparse recovery technique. In this case, the one-to-one mapping of Digital Elevation Model (DEM brakes down. To overcome this, an optimal DEM reconstruction method for LASAR based on the variational model is discussed in an effort to optimize the DEM and the associated scattering coefficient map, and to minimize the Mean Square Error (MSE. Using simulation experiments, it is found that the variational model is more suitable for DEM enhancement applications to all kinds of terrains compared with the Orthogonal Matching Pursuit (OMPand Least Absolute Shrinkage and Selection Operator (LASSO methods.

  13. Numerical computation methods for magnet design of spectrometer, accelerator and beam transport systems

    International Nuclear Information System (INIS)

    Fan Mingwu; Maio Yixin

    1986-01-01

    High calculation accuracy is expected in the design of spectrometer, accelerator or beam transport systems. Three dimensional electromagnetic field computation is needed in some cases. In solving these problems, numerical computation methods have been dominating in the area. Advantages and disadvantages among the methods are discussed and errors between computed and measured values are analysised. The application of making full use of these methods is discussed based on some practical models

  14. An FDTD method with FFT-accelerated exact absorbing boundary conditions

    KAUST Repository

    Sirenko, Kostyantyn

    2011-07-01

    An accurate and efficient finite-difference time-domain (FDTD) method for analyzing axially symmetric structures is presented. The method achieves its accuracy and efficiency using exact absorbing conditions (EACs) for terminating the computation domain and a blocked-FFT based scheme for accelerating the computation of the temporal convolutions present in non-local EACs. The method is shown to be especially useful in characterization of long-duration resonant wave interactions. © 2011 IEEE.

  15. A Spaceborne Synthetic Aperture Radar Partial Fixed-Point Imaging System Using a Field- Programmable Gate Array-Application-Specific Integrated Circuit Hybrid Heterogeneous Parallel Acceleration Technique.

    Science.gov (United States)

    Yang, Chen; Li, Bingyi; Chen, Liang; Wei, Chunpeng; Xie, Yizhuang; Chen, He; Yu, Wenyue

    2017-06-24

    With the development of satellite load technology and very large scale integrated (VLSI) circuit technology, onboard real-time synthetic aperture radar (SAR) imaging systems have become a solution for allowing rapid response to disasters. A key goal of the onboard SAR imaging system design is to achieve high real-time processing performance with severe size, weight, and power consumption constraints. In this paper, we analyse the computational burden of the commonly used chirp scaling (CS) SAR imaging algorithm. To reduce the system hardware cost, we propose a partial fixed-point processing scheme. The fast Fourier transform (FFT), which is the most computation-sensitive operation in the CS algorithm, is processed with fixed-point, while other operations are processed with single precision floating-point. With the proposed fixed-point processing error propagation model, the fixed-point processing word length is determined. The fidelity and accuracy relative to conventional ground-based software processors is verified by evaluating both the point target imaging quality and the actual scene imaging quality. As a proof of concept, a field- programmable gate array-application-specific integrated circuit (FPGA-ASIC) hybrid heterogeneous parallel accelerating architecture is designed and realized. The customized fixed-point FFT is implemented using the 130 nm complementary metal oxide semiconductor (CMOS) technology as a co-processor of the Xilinx xc6vlx760t FPGA. A single processing board requires 12 s and consumes 21 W to focus a 50-km swath width, 5-m resolution stripmap SAR raw data with a granularity of 16,384 × 16,384.

  16. A Spaceborne Synthetic Aperture Radar Partial Fixed-Point Imaging System Using a Field- Programmable Gate Array−Application-Specific Integrated Circuit Hybrid Heterogeneous Parallel Acceleration Technique

    Directory of Open Access Journals (Sweden)

    Chen Yang

    2017-06-01

    Full Text Available With the development of satellite load technology and very large scale integrated (VLSI circuit technology, onboard real-time synthetic aperture radar (SAR imaging systems have become a solution for allowing rapid response to disasters. A key goal of the onboard SAR imaging system design is to achieve high real-time processing performance with severe size, weight, and power consumption constraints. In this paper, we analyse the computational burden of the commonly used chirp scaling (CS SAR imaging algorithm. To reduce the system hardware cost, we propose a partial fixed-point processing scheme. The fast Fourier transform (FFT, which is the most computation-sensitive operation in the CS algorithm, is processed with fixed-point, while other operations are processed with single precision floating-point. With the proposed fixed-point processing error propagation model, the fixed-point processing word length is determined. The fidelity and accuracy relative to conventional ground-based software processors is verified by evaluating both the point target imaging quality and the actual scene imaging quality. As a proof of concept, a field- programmable gate array−application-specific integrated circuit (FPGA-ASIC hybrid heterogeneous parallel accelerating architecture is designed and realized. The customized fixed-point FFT is implemented using the 130 nm complementary metal oxide semiconductor (CMOS technology as a co-processor of the Xilinx xc6vlx760t FPGA. A single processing board requires 12 s and consumes 21 W to focus a 50-km swath width, 5-m resolution stripmap SAR raw data with a granularity of 16,384 × 16,384.

  17. A two-step iterative method and its acceleration for outer inverses

    Indian Academy of Sciences (India)

    A two-step iterative method and its accelerated version for approximating outer inverse A2 T,S of an arbitrary matrix A are proposed. A convergence theorem for its existence is established. The rigorous error bounds are derived. Numerical experiments involving singular square, rectangular, random matrices and a sparse ...

  18. Implementing Expertise-Based Training Methods to Accelerate the Development of Peer Academic Coaches

    Science.gov (United States)

    Blair, Lisa

    2016-01-01

    The field of expertise studies offers several models from which to develop training programs that accelerate the development of novice performers in a variety of domains. This research study implemented two methods of expertise-based training in a course to develop undergraduate peer academic coaches through a ten-week program. An existing…

  19. Effect of processing method on accelerated weathering of wood-flour/HDPE composites

    Science.gov (United States)

    Nicole M. Stark; Laurent M. Matuana; Craig M. Clemons

    2003-01-01

    Wood-plastic lumber is promoted as a low maintenance high-durability product. When exposed to accelerated weathering, however, wood-plastic composites may experience a color change and/or loss in mechanical properties. Different methods of manufacturing wood-plastic composites lead to different surface characteristics, which can influence weathering, In this study, 50...

  20. A micro-macro acceleration method for the Monte Carlo simulation of stochastic differential equations

    DEFF Research Database (Denmark)

    Debrabant, Kristian; Samaey, Giovanni; Zieliński, Przemysław

    2017-01-01

    We present and analyse a micro-macro acceleration method for the Monte Carlo simulation of stochastic differential equations with separation between the (fast) time-scale of individual trajectories and the (slow) time-scale of the macroscopic function of interest. The algorithm combines short...

  1. Control Methods of the Switched Reluctance Motor in Electric Vehicle During Acceleration

    Directory of Open Access Journals (Sweden)

    Fathy El Sayed ABDEL-KADER

    2012-08-01

    Full Text Available In this paper, the equations describing the performance of the electric vehicle are derived. Performance characteristics for each part in the vehicle system are obtained when the vehicle is accelerated under voltage, turn on and turn off angle control. A comparison between the different methods of control is established.

  2. Accelerated algorithm for three-dimensional computer generated hologram based on the ray-tracing method

    Science.gov (United States)

    Xie, Z. W.; Zang, J. L.; Zhang, Y.

    2013-06-01

    An accelerated algorithm for three-dimensional computer generated holograms (CGHs) based on the ray-tracing method is proposed. The complex amplitude distribution from the center point of an object is calculated in advance and the field distributions of rest points on the hologram plane can be given by doing a small translation and an aberration to the pre-calculated field. A static two-dimensional car, a three-dimensional teapot, and a dynamic three-dimensional rotating teapot are reconstructed from CGHs calculated with the accelerated algorithm to prove its validity. The simulation results demonstrate that the accelerated algorithm is eight times faster than the conventional ray-tracing algorithm.

  3. Novel methods for evaluation of the Reynolds number of synthetic jets

    Czech Academy of Sciences Publication Activity Database

    Kordík, Jozef; Broučková, Zuzana; Vít, T.; Pavelka, Miroslav; Trávníček, Zdeněk

    2014-01-01

    Roč. 55, č. 6 (2014), 1757_1-1757_16 ISSN 0723-4864 R&D Projects: GA ČR GPP101/12/P556 Institutional support: RVO:61388998 Keywords : synthetic jet * synthetic jet actuator * Reynolds number Subject RIV: BK - Fluid Dynamics Impact factor: 1.670, year: 2014 http://link.springer.com/article/10.1007%2Fs00348-014-1757-x

  4. Method for pulse to pulse dose reproducibility applied to electron linear accelerators

    International Nuclear Information System (INIS)

    Ighigeanu, D.; Martin, D.; Oproiu, C.; Cirstea, E.; Craciun, G.

    2002-01-01

    An original method for obtaining programmed beam single shots and pulse trains with programmed pulse number, pulse repetition frequency, pulse duration and pulse dose is presented. It is particularly useful for automatic control of absorbed dose rate level, irradiation process control as well as in pulse radiolysis studies, single pulse dose measurement or for research experiments where pulse-to-pulse dose reproducibility is required. This method is applied to the electron linear accelerators, ALIN-10 of 6.23 MeV and 82 W and ALID-7, of 5.5 MeV and 670 W, built in NILPRP. In order to implement this method, the accelerator triggering system (ATS) consists of two branches: the gun branch and the magnetron branch. ATS, which synchronizes all the system units, delivers trigger pulses at a programmed repetition rate (up to 250 pulses/s) to the gun (80 kV, 10 A and 4 ms) and magnetron (45 kV, 100 A, and 4 ms).The accelerated electron beam existence is determined by the electron gun and magnetron pulses overlapping. The method consists in controlling the overlapping of pulses in order to deliver the beam in the desired sequence. This control is implemented by a discrete pulse position modulation of gun and/or magnetron pulses. The instabilities of the gun and magnetron transient regimes are avoided by operating the accelerator with no accelerated beam for a certain time. At the operator 'beam start' command, the ATS controls electron gun and magnetron pulses overlapping and the linac beam is generated. The pulse-to-pulse absorbed dose variation is thus considerably reduced. Programmed absorbed dose, irradiation time, beam pulse number or other external events may interrupt the coincidence between the gun and magnetron pulses. Slow absorbed dose variation is compensated by the control of the pulse duration and repetition frequency. Two methods are reported in the electron linear accelerators' development for obtaining the pulse to pulse dose reproducibility: the method

  5. Elementary and advanced Lie algebraic methods with applications to accelerator design, electron microscopes, and light optics

    International Nuclear Information System (INIS)

    Dragt, A.J.

    1987-01-01

    A review is given of elementary Lie algebraic methods for treating Hamiltonian systems. This review is followed by a brief exposition of advanced Lie algebraic methods including resonance bases and conjugacy theorems. Finally, applications are made to the design of third-order achromats for use in accelerators, to the design of subangstroem resolution electron microscopes, and to the classification and study of high order aberrations in light optics. (orig.)

  6. An improved method to accurately calibrate the gantry angle indicators of the radiotherapy linear accelerators

    International Nuclear Information System (INIS)

    Chang Liyun; Ho, S.-Y.; Du, Y.-C.; Lin, C.-M.; Chen Tainsong

    2007-01-01

    The calibration of the gantry angle indicator is an important and basic quality assurance (QA) item for the radiotherapy linear accelerator. In this study, we propose a new and practical method, which uses only the digital level, V-film, and general solid phantoms. By taking the star shot only, we can accurately calculate the true gantry angle according to the geometry of the film setup. The results on our machine showed that the gantry angle was shifted by -0.11 deg. compared with the digital indicator, and the standard deviation was within 0.05 deg. This method can also be used for the simulator. In conclusion, this proposed method could be adopted as an annual QA item for mechanical QA of the accelerator

  7. Beam-Based Error Identification and Correction Methods for Particle Accelerators

    CERN Document Server

    AUTHOR|(SzGeCERN)692826; Tomas, Rogelio; Nilsson, Thomas

    2014-06-10

    Modern particle accelerators have tight tolerances on the acceptable deviation from their desired machine parameters. The control of the parameters is of crucial importance for safe machine operation and performance. This thesis focuses on beam-based methods and algorithms to identify and correct errors in particle accelerators. The optics measurements and corrections of the Large Hadron Collider (LHC), which resulted in an unprecedented low β-beat for a hadron collider is described. The transverse coupling is another parameter which is of importance to control. Improvement in the reconstruction of the coupling from turn-by-turn data has resulted in a significant decrease of the measurement uncertainty. An automatic coupling correction method, which is based on the injected beam oscillations, has been successfully used in normal operation of the LHC. Furthermore, a new method to measure and correct chromatic coupling that was applied to the LHC, is described. It resulted in a decrease of the chromatic coupli...

  8. Ant colony method to control variance reduction techniques in the Monte Carlo simulation of clinical electron linear accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Pareja, S. [Servicio de Radiofisica Hospitalaria, Hospital Regional Universitario ' Carlos Haya' , Avda. Carlos Haya, s/n, E-29010 Malaga (Spain)], E-mail: garciapareja@gmail.com; Vilches, M. [Servicio de Fisica y Proteccion Radiologica, Hospital Regional Universitario ' Virgen de las Nieves' , Avda. de las Fuerzas Armadas, 2, E-18014 Granada (Spain); Lallena, A.M. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain)

    2007-09-21

    The ant colony method is used to control the application of variance reduction techniques to the simulation of clinical electron linear accelerators of use in cancer therapy. In particular, splitting and Russian roulette, two standard variance reduction methods, are considered. The approach can be applied to any accelerator in a straightforward way and permits, in addition, to investigate the 'hot' regions of the accelerator, an information which is basic to develop a source model for this therapy tool.

  9. Ant colony method to control variance reduction techniques in the Monte Carlo simulation of clinical electron linear accelerators

    International Nuclear Information System (INIS)

    Garcia-Pareja, S.; Vilches, M.; Lallena, A.M.

    2007-01-01

    The ant colony method is used to control the application of variance reduction techniques to the simulation of clinical electron linear accelerators of use in cancer therapy. In particular, splitting and Russian roulette, two standard variance reduction methods, are considered. The approach can be applied to any accelerator in a straightforward way and permits, in addition, to investigate the 'hot' regions of the accelerator, an information which is basic to develop a source model for this therapy tool

  10. A Vector Flow Imaging Method for Portable Ultrasound Using Synthetic Aperture Sequential Beamforming.

    Science.gov (United States)

    Di Ianni, Tommaso; Villagomez Hoyos, Carlos Armando; Ewertsen, Caroline; Kjeldsen, Thomas Kim; Mosegaard, Jesper; Nielsen, Michael Bachmann; Jensen, Jorgen Arendt

    2017-11-01

    This paper presents a vector flow imaging method for the integration of quantitative blood flow imaging in portable ultrasound systems. The method combines directional transverse oscillation (TO) and synthetic aperture sequential beamforming to yield continuous velocity estimation in the whole imaging region. Six focused emissions are used to create a high-resolution image (HRI), and a dual-stage beamforming approach is used to lower the data throughput between the probe and the processing unit. The transmit/receive focal points are laterally separated to obtain a TO in the HRI that allows for the velocity estimation along the lateral and axial directions using a phase-shift estimator. The performance of the method was investigated with constant flow measurements in a flow rig system using the SARUS scanner and a 4.1-MHz linear array. A sequence was designed with interleaved B-mode and flow emissions to obtain continuous data acquisition. A parametric study was carried out to evaluate the effect of critical parameters. The vessel was placed at depths from 20 to 40 mm, with beam-to-flow angles of 65°, 75°, and 90°. For the lateral velocities at 20 mm, a bias between -5% and -6.2% was obtained, and the standard deviation (SD) was between 6% and 9.6%. The axial bias was lower than 1% with an SD around 2%. The mean estimated angles were 66.70° ± 2.86°, 72.65° ± 2.48°, and 89.13° ± 0.79° for the three cases. A proof-of-concept demonstration of the real-time processing and wireless transmission was tested in a commercial tablet obtaining a frame rate of 27 frames/s and a data rate of 14 MB/s. An in vivo measurement of a common carotid artery of a healthy volunteer was finally performed to show the potential of the method in a realistic setting. The relative SD averaged over a cardiac cycle was 4.33%.

  11. TU-AB-BRA-02: An Efficient Atlas-Based Synthetic CT Generation Method

    Energy Technology Data Exchange (ETDEWEB)

    Han, X [Elekta Inc., Maryland Heights, MO (United States)

    2016-06-15

    Purpose: A major obstacle for MR-only radiotherapy is the need to generate an accurate synthetic CT (sCT) from MR image(s) of a patient for the purposes of dose calculation and DRR generation. We propose here an accurate and efficient atlas-based sCT generation method, which has a computation speed largely independent of the number of atlases used. Methods: Atlas-based sCT generation requires a set of atlases with co-registered CT and MR images. Unlike existing methods that align each atlas to the new patient independently, we first create an average atlas and pre-align every atlas to the average atlas space. When a new patient arrives, we compute only one deformable image registration to align the patient MR image to the average atlas, which indirectly aligns the patient to all pre-aligned atlases. A patch-based non-local weighted fusion is performed in the average atlas space to generate the sCT for the patient, which is then warped back to the original patient space. We further adapt a PatchMatch algorithm that can quickly find top matches between patches of the patient image and all atlas images, which makes the patch fusion step also independent of the number of atlases used. Results: Nineteen brain tumour patients with both CT and T1-weighted MR images are used as testing data and a leave-one-out validation is performed. Each sCT generated is compared against the original CT image of the same patient on a voxel-by-voxel basis. The proposed method produces a mean absolute error (MAE) of 98.6±26.9 HU overall. The accuracy is comparable with a conventional implementation scheme, but the computation time is reduced from over an hour to four minutes. Conclusion: An average atlas space patch fusion approach can produce highly accurate sCT estimations very efficiently. Further validation on dose computation accuracy and using a larger patient cohort is warranted. The author is a full time employee of Elekta, Inc.

  12. An iterative method for accelerated degradation testing data of smart electricity meter

    Science.gov (United States)

    Wang, Xiaoming; Xie, Jinzhe

    2017-01-01

    In order to evaluate the performance of smart electricity meter (SEM), we must spend a lot of time censoring its status. For example, if we assess to the meter stability of the SEM which needs several years at least according to the standards. So accelerated degradation testing (ADT) is a useful method to assess the performance of the SEM. As we known, the Wiener process is a prevalent method to interpret the performance degradation. This paper proposes an iterative method for ADT data of SEM. The simulation study verifies the application and superiority of the proposed model than other ADT methods.

  13. A new approach to acceleration of methods of creating graphic animation in architecture

    Directory of Open Access Journals (Sweden)

    Radojčić Marko

    2011-01-01

    Full Text Available Modern approach to technical visualization methods is not possible without using contemporary 3D animation methods. Obvious need of demonstrating the results of design process in civil engineering, architecture and other technical areas still includes classical time consuming and non-flexible methods that require the process to restart in case of making some changes on the design. This method proposes changes based on some already available open source software packages and components that can be modified in a manner that unlocks accelerated technical visualizations in real time and with instant modifications along with efficiently usage of the processing power of contemporary graphics processing units.

  14. Reading comprehension of czech pupils at the beginning of primary school: comparison betweenanalytic-synthetic and genetic methods

    OpenAIRE

    Kucharska, Anna; Spackova, Klára

    2014-01-01

    In Czech schools two teaching methods of reading are used: the analytic-synthetic (conventional) and genetic (created in the 1990s). They differ in theoretical foundations and in methodology. The aim of this paper is to describe the above mentioned theoretical approaches and present the results of study that followed the differences in the development of initial reading skills between these methods. A total of 452 first grade children (age 6-8) were assessed by a battery of ...

  15. A systematic examination of colour development in synthetic ultramarine according to historical methods.

    Directory of Open Access Journals (Sweden)

    Ian Hamerton

    Full Text Available A number of historical texts are investigated to ascertain the optimum conditions for the preparation of synthetic ultramarine, using preparative methods that would have been available to alchemists and colour chemists of the nineteenth century. The effect of varying the proportion of sulphur in the starting material on the colour of the final product is investigated. The optimum preparation involves heating a homogenised, pelletised mixture of kaolin (100 parts, sodium carbonate (100 parts, bitumen emulsion (or any 'sticky' carbon source (12 parts and sulphur (60 parts at 750°C for ca. 4 hours. At this stage the ingress of air should be limited. The sample is allowed to cool in the furnace to 500°C, the ingress of air is permitted and additional sulphur (30 parts is introduced before a second calcination step is undertaken at 500°C for two hours. The products obtained from the optimum synthesis have CIE ranges of x  = 0.2945-0.3125, y  = 0.2219-0.2617, Y  = 0.4257-0.4836, L* = 3.8455-4.3682, a*  = 4.2763-7.6943, b* = -7.6772-(-3.3033, L  = 3.8455-4.3682, C = 5.3964-10.8693, h = 315.0636-322.2562. The values are calculated using UV/visible near infrared spectra using Lazurite [1], under D65 illumination, and the 1931 2° observer.

  16. A simple method for the determination of synthetic spirit in some alcoholic beverages

    International Nuclear Information System (INIS)

    Majerova, P.; Fiser, B.; Leseticky, L.

    2002-01-01

    Measurement of carbon C-14 can be used to distinguish between natural and synthetic alcohol. Natural ethanol produced by fermentation of sugar contains approximately 16.13 DPM (0,27 Bq) per gram of carbon, synthetic ethanol should contain no carbon-14. Natural C-14 content can be determined precisely and conveniently by liquid scintillation counting. Various scintillation cocktails were tested and the best results were achieved with PCS. The optimum measurement conditions were also identified. Samples of spirits were fractionated on a short distillation column and the resulting 96% ethanol was measured. For comparison was distilled and measured A 35% aqueous solution of natural ethanol was also distilled and measured for a comparison. The natural-to-synthetic ethanol ratio was obtained for a series of commercial spirits. (P.A.)

  17. Synthetic Methods for Ester Bond Formation and Conformational Analysis of Ester-Containing Carbohydrates

    Science.gov (United States)

    Hackbusch, Sven

    This dissertation encompasses work related to synthetic methods for the formation of ester linkages in organic compounds, as well as the investigation of the conformational influence of the ester functional group on the flexibility of inter-saccharide linkages, specifically, and the solution phase structure of ester-containing carbohydrate derivatives, in general. Stereoselective reactions are an important part of the field of asymmetric synthesis and an understanding of their underlying mechanistic principles is essential for rational method development. Here, the exploration of a diastereoselective O-acylation reaction on a trans-2-substituted cyclohexanol scaffold is presented, along with possible reasons for the observed reversal of stereoselectivity dependent on the presence or absence of an achiral amine catalyst. In particular, this work establishes a structure-activity relationship with regard to the trans-2-substituent and its role as a chiral auxiliary in the reversal of diastereoselectivity. In the second part, the synthesis of various ester-linked carbohydrate derivatives, and their conformational analysis is presented. Using multidimensional NMR experiments and computational methods, the compounds' solution-phase structures were established and the effect of the ester functional group on the molecules' flexibility and three-dimensional (3D) structure was investigated and compared to ether or glycosidic linkages. To aid in this, a novel Karplus equation for the C(sp2)OCH angle in ester-linked carbohydrates was developed on the basis of a model ester-linked carbohydrate. This equation describes the sinusoidal relationship between the C(sp2)OCH dihedral angle and the corresponding 3JCH coupling constant that can be determined from a J-HMBC NMR experiment. The insights from this research will be useful in describing the 3D structure of naturally occurring and lab-made ester-linked derivatives of carbohydrates, as well as guiding the de novo-design of

  18. New Approaches in Modeling Multiphase Flows and Dispersion in Turbulence, Fractal Methods and Synthetic Turbulence

    CERN Document Server

    Nicolleau, FCGA; Redondo, J-M

    2012-01-01

    This book contains a collection of the main contributions from the first five workshops held by Ercoftac Special Interest Group on Synthetic Turbulence Models (SIG42. It is intended as an illustration of the sig's activities and of the latest developments in the field. This volume investigates the use of Kinematic Simulation (KS) and other synthetic turbulence models for the particular application to environmental flows. This volume offers the best syntheses on the research status in KS, which is widely used in various domains, including Lagrangian aspects in turbulence mixing/stirring, partic

  19. A screening method of oil-soluble synthetic dyes in chilli products based on multi-wavelength chromatographic fingerprints comparison.

    Science.gov (United States)

    Zhu, Yonghong; Wu, Yanlei; Zhou, Chunjie; Zhao, Bo; Yun, Wen; Huang, Siyu; Tao, Peng; Tu, Dawei; Chen, Shiqi

    2016-02-01

    A multi-wavelength HPLC fingerprint comparison method was proposed for the screening of oil-soluble synthetic dyes in chilli products. The screening was based on the fingerprint differences of normal unadulterated chilli sample with tested chilli samples. The samples were extracted with acetone and fingerprinted by HPLC under four visible light wavelengths (450 nm, 490 nm, 520 nm, and 620 nm). It was found that the fingerprints of different chilli product samples had a relatively fixed number of peaks and stable retention time. When 16 kinds of known synthetic dyes were used as model analytes to assess the screening efficiency, 14 of them could be screened using fingerprint comparison method, with LOD of 0.40-2.41 mg/kg. The new screening method was simple and had the possibility of finding existence of the adulterated dyes which could not be identified using known standard analytes as control. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Investigation of Synthetic Jets Efficiency to Control Cavity Flotation with Subsonic External Flow by High-Resolution RANS / ILES Method

    Directory of Open Access Journals (Sweden)

    D. A. Lyubimov

    2015-01-01

    Full Text Available Cavities often found in airplanes: a niche for the landing gear, various weapons, etc. Reducing fluctuations of pressure and temperature in the cavity is a relevant practical problem. The article presents simulation results of external subsonic flow around the cavity (M = 0.85, T = 300K. . Calculations were performed using the high-resolution RANS/ILES (Reynolds Averaged Navier-Stokes - RANS, Implicit Large Eddy Simulation - ILES method. To control flow the authors propose to use synthetic jets. Synthetic jets are produced by periodic ejection and suction of fluid from a slot induced by the movement of a diaphragm (generator of synthetic jets inside a cavity. They are compact and efficient and do not require a special working body and the ways for its supply. Instead of calculating the flow in the synthetic jet generator was used the modified boundary condition on the wall where the output slots was positioned. Under consideration there were two variants of slots for synthetic jets output: in front of the cavity and inside the cavity on the front wall. The frequency and amplitude values of the synthetic jet specified a mode of each jet. For a jet inside the cavity two modes have been reviewed, namely: 100 Hz and 50m/s, 200Hz and 50m/s. For jet in front of the cavity three modes have been reviewed, specifically: 20Hz and 20m/s, 100Hz and 50m/s, 200Hz and 50m/s. Analysis of calculation results showed that for all modes under examination, the synthetic jets reduced fluctuation of static pressure and temperature on the bottom and back walls of the cavity. The mode with parameters 200Hz, 50 m/s and synthetic jet located in front of the cavity was the most efficient. Furthermore, we compared the results of calculations for two-and three-dimensional cavities, which have the same length and depth. Research has shown that the simplified quasi-two-dimensional calculations cannot be used to evaluate the pressure and temperature fluctuations. This is due to

  1. Acceleration of step and linear discontinuous schemes for the method of characteristics in DRAGON5

    Directory of Open Access Journals (Sweden)

    Alain Hébert

    2017-09-01

    Full Text Available The applicability of the algebraic collapsing acceleration (ACA technique to the method of characteristics (MOC in cases with scattering anisotropy and/or linear sources was investigated. Previously, the ACA was proven successful in cases with isotropic scattering and uniform (step sources. A presentation is first made of the MOC implementation, available in the DRAGON5 code. Two categories of schemes are available for integrating the propagation equations: (1 the first category is based on exact integration and leads to the classical step characteristics (SC and linear discontinuous characteristics (LDC schemes and (2 the second category leads to diamond differencing schemes of various orders in space. The acceleration of these MOC schemes using a combination of the generalized minimal residual [GMRES(m] method preconditioned with the ACA technique was focused on. Numerical results are provided for a two-dimensional (2D eight-symmetry pressurized water reactor (PWR assembly mockup in the context of the DRAGON5 code.

  2. Feedback control of torsion balance in measurement of gravitational constant G with angular acceleration method.

    Science.gov (United States)

    Quan, Li-Di; Xue, Chao; Shao, Cheng-Gang; Yang, Shan-Qing; Tu, Liang-Cheng; Wang, Yong-Ji; Luo, Jun

    2014-01-01

    The performance of the feedback control system is of central importance in the measurement of the Newton's gravitational constant G with angular acceleration method. In this paper, a PID (Proportion-Integration-Differentiation) feedback loop is discussed in detail. Experimental results show that, with the feedback control activated, the twist angle of the torsion balance is limited to [Formula: see text] at the signal frequency of 2 mHz, which contributes a [Formula: see text] uncertainty to the G value.

  3. A Differential Equation for Modeling Nesterov's Accelerated Gradient Method: Theory and Insights

    OpenAIRE

    Su, Weijie; Boyd, Stephen; Candes, Emmanuel J.

    2015-01-01

    We derive a second-order ordinary differential equation (ODE) which is the limit of Nesterov's accelerated gradient method. This ODE exhibits approximate equivalence to Nesterov's scheme and thus can serve as a tool for analysis. We show that the continuous time ODE allows for a better understanding of Nesterov's scheme. As a byproduct, we obtain a family of schemes with similar convergence rates. The ODE interpretation also suggests restarting Nesterov's scheme leading to an algorithm, which...

  4. Subspace accelerated inexact Newton method for large scale wave functions calculations in Density Functional Theory

    Energy Technology Data Exchange (ETDEWEB)

    Fattebert, J

    2008-07-29

    We describe an iterative algorithm to solve electronic structure problems in Density Functional Theory. The approach is presented as a Subspace Accelerated Inexact Newton (SAIN) solver for the non-linear Kohn-Sham equations. It is related to a class of iterative algorithms known as RMM-DIIS in the electronic structure community. The method is illustrated with examples of real applications using a finite difference discretization and multigrid preconditioning.

  5. Development and design of nanomaterial reagents in conjunction with new methods for their synthetic applications

    Science.gov (United States)

    Kwaramba, Farai Brian

    This Ph.D. deals with the integration of nanotechnology with organometallic/ organic synthetic technologies. The first part of this research sought to develop a library of novel molecular gears programmed to exploit photo-switching and electrostatic repulsion to control the molecular rotation of covalently linked triptypyrazines. Incorporation of these two modes allows for control of triptycene based gear systems using unexplored external methods. The triptypyrazine was an attractive scaffold because of its intrinsic pH and electrochemical activity, thus providing a novel construct for controlling molecular motion. This design finds relevance in the fabrication of nano-electromechanical devices and understanding controlled molecular motion. This Ph.D. also sought to address the need to generate and recycle low cost hydrosilylation catalysts. Metal nanoparticle catalysts can potentially meet this need due to their high surface area and reactivity. Their morphology and surface texture provide avenues for selectivity in reactions. Metal-nanoparticles on a silicon matrix can be formed by reducing metal salts with silicon hydrides. Investigations towards iron-nanoparticle catalyzed hydrosilylation of unsaturated bonds were conducted. Furthermore, this research sought to develop highly functionalized silanes, as guiding scaffolds for generating chiral silicon hydrides. Fabrication of metal-nanoparticle catalysts with the same, could install surface definition on these heterogeneous green catalysts, thus allowing selectivity in their catalysis. A bottom up approach to nanofabrication, started with the generation of a library of highly functionalized alkynyl-silane building blocks using the hydrosilylation reaction. Hydrosilylation of carbon-carbon and carbon-heteroatom unsaturated bonds has proven to be an important reaction in organic syntheses. Additionally, silicon tethers have been utilized in complex organic syntheses as a way to increase reaction rates, and

  6. Optimal contrast enhancement achieved by the synthetic method for bone and tissue separation based on a dual-energy radiographic system

    Science.gov (United States)

    Kim, D.-H.; Lee, Y.-J.; Jeon, P.-H.; Jo, B.-D.; Kim, H.-J.

    2013-07-01

    In dual-energy digital radiography (DEDR), the energy subtraction and equivalent thickness methods have been used for detecting thorax lesions. However, the image contrast of the energy subtraction method is low in comparion with that of the equivalent thickness and synthetic methods. Therefore, we applied the equivalent thickness and synthetic methods to material separation to enhance the bone and tissue contrast, and these results were compared with the results of the energy subtraction method in a chest DEDR system. The purpose of this work was to evaluate the image quality of the energy subtraction, equivalent thickness, and synthetic methods. In the energy subtraction method, the optimal weighting factors were selected for bone and tissue visualization, respectively. The equivalent thickness was obtained with a calibration procedure by using combinations of aluminum and polymethyl methacrylate (PMMA) blocks. The synthetic images were acquired with the known equation from the results of the equivalent thickness method. According to these results, the contrast-to-noise-ratio (CNR) values using the equivalent thickness and synthetic methods were improved than those obtained with the energy subtraction method in both aluminum and PMMA enhancement trial. In a cylindrical phantom study, the equivalent thickness and the synthetic method improved the contrast better than energy subtraction method. The synthetic method supplements the air shadows shown in the equivalent thickness method. We compared the enhanced images of bone and tissue with the energy subtraction, equivalent thickness, and synthetic methods. Our results showed that the effects of the synthetic method can improve the image contrast on both bone and tissue and overcome the bone shadows in tissue images in a DEDR system.

  7. Chemical and Physical Analysis Methods for Characterizing Tire Crumb Rubber Used in Synthetic Turf Fields

    Science.gov (United States)

    Tire crumb rubber from recycled tires is widely used as infill material in synthetic turf fields in the United States. Recycled crumb rubber is a complex and potentially variable matrix with many metal, VOC, and SVOC constituents, presenting challenges for characterization and ex...

  8. Accelerated gradient methods for total-variation-based CT image reconstruction

    DEFF Research Database (Denmark)

    Jørgensen, Jakob Heide; Jensen, Tobias Lindstrøm; Hansen, Per Christian

    2011-01-01

    incorporates several heuristics from the optimization literature such as Barzilai-Borwein (BB) step size selection and nonmonotone line search. The latter uses a cleverly chosen sequence of auxiliary points to achieve a better convergence rate. The methods are memory efficient and equipped with a stopping...... reconstruction can in principle be found by any optimization method, but in practice the large scale of the systems arising in CT image reconstruction preclude the use of memory-demanding methods such as Newton’s method. The simple gradient method has much lower memory requirements, but exhibits slow convergence....... In the present work we address the question of how to reduce the number of gradient method iterations needed to achieve a high-accuracy TV reconstruction. We consider the use of two accelerated gradient-based methods, GPBB and UPN, to solve the 3D-TV minimization problem in CT image reconstruction. The former...

  9. Novel Synthetic Methods and Characterization Studies of Niobium-Disulfide in Multiple Geometries

    Science.gov (United States)

    Cooper, Brian C.

    Since the discovery of graphene, there has been a marked uptick in the rate of research conducted on layered 2D systems. Although much of this work has focused on understanding the properties of the semiconducting members of this group, earnest efforts towards gaining further insight into the physical properties of the non-semiconducting members has also been made. NbS 2, a member of the latter group, offers wide spectrum of physical behavior for study as it undergoes multiple phase transitions from a metal at room temperature to a dual-band superconductor a very. At room temperature this material exhibits metallic character, while at lower temperatures in the range of 30K it undergoes a phase transition to a charge density wave state. It , and that is a undergoes several state transitions within certain temperature regimes Though the effects that quantum constraints impose on Cooper pairs limited to planar transport have been a long established area of research, it has only been in recent years that strides have been made into understanding the nature of quantum confinement on dual-band superconductors. In the contents of this thesis, I provide a thorough account of the development for a novel technique for the synthesis of NbS2 and this technique's evolution through the careful characterization studies performed on the materials resulting from each successive trial. The thesis opens with a brief introduction and relevant historical account of the study of graphene and other 2D layered materials to provide the context from which the reader will understand the motivation for this work. Protocols and parameters developed from the first set of successful experiments, provided the backbone for a reliable synthetic technique for growth of polycrystalline NbS2. The 3R polytype of NbS2 was the overwhelmingly dominant phase within the resultant materials grown during the first trials, but the desire to produce results rich in the 2H-NbS2 polytype prompted a series of

  10. A method for the analysis of natural and synthetic folate in foods.

    Science.gov (United States)

    Doherty, Robert F; Beecher, Gary R

    2003-01-15

    The essentiality of dietary folates for human beings has been known for many years. Over the shorter term, biological activities associated with several human maladies and the attenuation of biomarkers for several chronic diseases also have been assigned to folates. In the United States, these observations have led to the addition of folic acid to several foods and food ingredients (food fortification) and to dietary recommendations that assign biological activity to each of the forms of folate in the food supply. There currently is unavailable a robust, instrumental procedure that will distinguish between naturally occurring food folates and synthetic folic acid as part of the routine analysis of foods. The procedure proposed in this publication is unique in that it uses "off-the-shelf" supplies and instrumentation, to the extent possible, and was developed with "normal" corporate work schedules in mind. This method takes advantage of the tri-enzyme food digestion and folate deconjugation steps but was optimized with a commercially available rat plasma as the source of conjugase. A high-capacity styrene-divinylbenzene-based solid-phase extraction column was identified, and conditions were developed for quantitative recovery of 5-methyltetrahydrofolate and folic acid (FA) with it. The various forms of food folates are separated on a C-18 high-performance liquid chromatography (HPLC) column which is resistant to degradation at low pH. As a result, the mobile phase was simplified to a gradient of low-pH phosphate buffer (pH 2.2) and acetonitrile. Although FA does not exhibit fluorescence, a UV-induced photolysis system was added, which is controlled by the HPLC system, so that an appropriate segment of the HPLC column effluent is subjected to photolytic conditions and, thereby, FA can be measured as a fluorescent product. The application of the system was verified by analyzing several certified reference materials and foods and comparing results with certified values

  11. Long-time atomistic dynamics through a new self-adaptive accelerated molecular dynamics method

    Energy Technology Data Exchange (ETDEWEB)

    Gao, N.; Yang, L.; Gao, F.; Kurtz, R. J.; West, D.; Zhang, S.

    2017-02-27

    A self-adaptive accelerated molecular dynamics method is developed to model infrequent atomic- scale events, especially those events that occur on a rugged free-energy surface. Key in the new development is the use of the total displacement of the system at a given temperature to construct a boost-potential, which is slowly increased to accelerate the dynamics. The temperature is slowly increased to accelerate the dynamics. By allowing the system to evolve from one steady-state con guration to another by overcoming the transition state, this self-evolving approach makes it possible to explore the coupled motion of species that migrate on vastly different time scales. The migrations of single vacancy (V) and small He-V clusters, and the growth of nano-sized He-V clusters in Fe for times in the order of seconds are studied by this new method. An interstitial- assisted mechanism is rst explored for the migration of a helium-rich He-V cluster, while a new two-component Ostwald ripening mechanism is suggested for He-V cluster growth.

  12. Novel methods in the Particle-In-Cell accelerator Code-Framework Warp

    Energy Technology Data Exchange (ETDEWEB)

    Vay, J-L [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Grote, D. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cohen, R. H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Friedman, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2012-12-26

    The Particle-In-Cell (PIC) Code-Framework Warp is being developed by the Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) to guide the development of accelerators that can deliver beams suitable for high-energy density experiments and implosion of inertial fusion capsules. It is also applied in various areas outside the Heavy Ion Fusion program to the study and design of existing and next-generation high-energy accelerators, including the study of electron cloud effects and laser wakefield acceleration for example. This study presents an overview of Warp's capabilities, summarizing recent original numerical methods that were developed by the HIFS-VNL (including PIC with adaptive mesh refinement, a large-timestep 'drift-Lorentz' mover for arbitrarily magnetized species, a relativistic Lorentz invariant leapfrog particle pusher, simulations in Lorentz-boosted frames, an electromagnetic solver with tunable numerical dispersion and efficient stride-based digital filtering), with special emphasis on the description of the mesh refinement capability. In addition, selected examples of the applications of the methods to the abovementioned fields are given.

  13. Dynamic Analysis of a Timoshenko Beam Subjected to an Accelerating Mass Using Spectral Element Method

    Directory of Open Access Journals (Sweden)

    Guangsong Chen

    2014-01-01

    Full Text Available This paper presents formulations for a Timoshenko beam subjected to an accelerating mass using spectral element method in time domain (TSEM. Vertical displacement and bending rotation of the beam were interpolated by Lagrange polynomials supported on the Gauss-Lobatto-Legendre (GLL points. By using GLL integration rule, the mass matrix was diagonal and the dynamic responses can be obtained efficiently and accurately. The results were compared with those obtained in the literature to verify the correctness. The variation of the vibration frequencies of the Timoshenko and moving mass system was researched. The effects of inertial force, centrifugal force, Coriolis force, and tangential force on a Timoshenko beam subjected to an accelerating mass were investigated.

  14. The fingerprint method for characterization of radioactive waste in hadron accelerators

    CERN Document Server

    Magistris, M

    2008-01-01

    Beam losses are responsible for material activation in most of the components of particle accelerators. The activation is caused by several nuclear processes and varies with the irradiation history and the characteristics of the material (namely chemical composition and size). Once at the end of their operational lifetime, these materials require radiological characterization. The radionuclide inventory depends on the particle spectrum, the irradiation history and the chemical composition of the material. As long as these factors are known and the material cross-sections are available, the induced radioactivity can be calculated analytically. However, these factors vary widely among different items of waste and sometimes they are only partially known. The European Laboratory for Particle Physics (CERN, Geneva) has been operating accelerators for high-energy physics for 50 years. Different methods for the evaluation of the radionuclide inventory are currently under investigation at CERN, including the so-calle...

  15. Multi-level nonlinear diffusion acceleration method for multigroup transport k-Eigenvalue problems

    International Nuclear Information System (INIS)

    Anistratov, Dmitriy Y.

    2011-01-01

    The nonlinear diffusion acceleration (NDA) method is an efficient and flexible transport iterative scheme for solving reactor-physics problems. This paper presents a fast iterative algorithm for solving multigroup neutron transport eigenvalue problems in 1D slab geometry. The proposed method is defined by a multi-level system of equations that includes multigroup and effective one-group low-order NDA equations. The Eigenvalue is evaluated in the exact projected solution space of smallest dimensionality, namely, by solving the effective one- group eigenvalue transport problem. Numerical results that illustrate performance of the new algorithm are demonstrated. (author)

  16. Numerical investigations on coupled heat transfer and synthetical performance of a pressurized volumetric receiver with MCRT–FVM method

    International Nuclear Information System (INIS)

    Cheng, Z.D.; He, Y.L.; Cui, F.Q.

    2013-01-01

    This paper presents an axisymmetric steady-state computational fluid dynamics model and further studies on the complex coupled heat transfer combined radiation–convection–conduction in the pressurized volumetric receiver (PVR), by combining the Finite Volume Method (FVM) and the Monte Carlo Ray-Trace (MCRT) method. Based on this, effects of geometric parameters of the compound parabolic concentrator (CPC) and properties of the porous absorber on synthetical characteristics and performance of the photo-thermal conversion process in the PVR are further analyzed and discussed detailedly. It is found that the solar flux density distributions are always very heterogeneous with large nonuniformities, and the variation trends of the corresponding temperature distributions are very similar to these but with much lower order of magnitude. The CPC shape determined by the CPC exit aperture has much larger effects on synthetical characteristics and performance of the PVR than that of the CPC entry aperture with a constant acceptance angle. And a suitable or optimal thickness of the porous absorber could be determined by examining where the drastic decreasing trends occur at the curves of variations of synthetical characteristics and performance with the porosity. - Highlights: ► An axisymmetric steady-state CFD model of PVR is presented with MCRT–FVM method. ► The complex coupled heat transfer and synthetical performance of the PVR are studied. ► The effects of geometric parameters and porous properties are analyzed and discussed. ► Solar flux and temperature in PVR are very heterogeneous with large nonuniformities. ► An optimal absorber thickness can be determined by examining the effects of porosity.

  17. Validated HPLC method for determination of caffeine level in human plasma using synthetic plasma: application to bioavailability studies.

    Science.gov (United States)

    Alvi, Syed N; Hammami, Muhammad M

    2011-04-01

    Several high-performance liquid chromatography (HPLC) methods have been described for the determination of caffeine in human plasma. However, none have been cross validated using synthetic plasma. The present study describes a simple and reliable HPLC method for the determination of the caffeine level in human plasma. Synthetic plasma was used to construct calibration curves and quality control samples to avoid interference by caffeine commonly present in donor's human plasma. After deproteination of plasma samples with perchloric acid, caffeine and antipyrine (internal standard, IS) were separated on a Waters Atlantis C18 column using a mobile phase of 15 mM potassium phosphate (pH 3.5) and acetonitrile (83:17, v/v), and monitored by photodiode array detector, with the wavelength set at 274 nm. The relationship between caffeine concentrations and peak area ratio (caffeine-IS) was linear over the range of 0.05-20 μg/mL. Inter-run coefficient of variation was ≤ 5.4% and ≤ 6.0% and bias was ≤ 3% and ≤ 7% using human and synthetic plasma, respectively. Mean extraction recovery from human plasma of caffeine and the IS was 91% and 86%, respectively. Caffeine in human plasma was stable for at least 24 h at room temperature or 12 weeks at -20 °C, and after three freeze-thaw cycles. The method was successfully applied to monitor caffeine levels in healthy volunteers with correction of caffeine levels using the mean ratio of the slopes of the calibration's curves constructed using human and synthetic plasma.

  18. Automated Method to Develop a Clark Synthetic Unit Hydrograph within ArcGIS

    Science.gov (United States)

    2015-08-01

    develop a synthetic unit hydrograph of a small watershed using readily available spatial data products, namely Digital Elevation Model ( DEM ), and...the spatial features of the watershed affect the runoff of the basin and therefore the unit hydrograph at the outlet of the basin . BACKGROUND...Modeling System (Scharffenberg and Fleming 2006). Within gauged basins , the unit hydrograph can be developed using observed storm events (precipitation

  19. Development of a synthetic cheese medium for fungi using chemometric methods

    DEFF Research Database (Denmark)

    Hansen, Birgitte Vedel; Nielsen, Per Væggemose

    1997-01-01

    , lactose, and casein. A robust, well-defined, and easily prepared cheese medium was developed for Penicillium commune, the most frequently occurring contaminant on semi-hard cheese. Growth experiments on the medium were repeatable and reproducible. The medium was also suitable for Penicillium camemberti......Growth, color formation, and mycotoxin production of six cheese-related fungi were studied on nine types of natural cheeses and 24 synthetic cheese media and compared using principal component analysis. The synthetic cheese media contained various amounts of Ca, K, Mg, Na, P, Fe, Cu, Zn, lactate....... The medium had the following composition: 100 g of casein, 8.3 g of 90% lactate (90%), 7.9 g of lactose, 7.3 g of CaCl2×2H2O, 2.6 g of MgSO4×7H2O, 26.0 g of NaCl, 20 g of agar, 0.025 g of FeSO4×7H2O, 0,004 g of CuSO4×5H2O, and water to a total weight of 1 kg. The synthetic cheese medium was less suitable...

  20. The Accelerated Window Work Method Using Vertical Formwork for Tall Residential Building Construction

    Directory of Open Access Journals (Sweden)

    Taehoon Kim

    2018-02-01

    Full Text Available In tall residential building construction, there is a process gap between the window work and the structural work. This process gap extends the total period of the project and increases its cost. In addition, as this process gap increases external exposure to noise and dust, it negatively affects the environment of a site and often causes civil complaints. This paper introduces a new window work process called the accelerated window work (AWW method, which minimizes the process gap and can reduce construction cost and duration and the number of civil complaints. We provide technical details and management elements of the AWW method with a case study that demonstrates the reductions in construction costs and duration compared with the conventional method. This work contributes to the body of knowledge in window work in tall buildings by introducing and validating a new window work method and process. The proposed method will be useful for practitioners who are under short-term constraints.

  1. Acceleration of the generalized global basis (GGB) method for nonlinear problems

    Science.gov (United States)

    Waisman, Haim; Fish, Jacob; Tuminaro, Raymond S.; Shadid, John N.

    2005-11-01

    Two heuristic strategies intended to enhance the performance of the generalized global basis (GGB) method [H. Waisman, J. Fish, R.S. Tuminaro, J. Shadid, The Generalized Global Basis (GGB) method, International Journal for Numerical Methods in Engineering 61(8), 1243-1269] applied to nonlinear systems are presented. The standard GGB accelerates a multigrid scheme by an additional coarse grid correction that filters out slowly converging modes. This correction requires a potentially costly eigen calculation. This paper considers reusing previously computed eigenspace information. The GGB α scheme enriches the prolongation operator with new eigenvectors while the modified method (MGGB) selectively reuses the same prolongation. Both methods use the criteria of principal angles between subspaces spanned between the previous and current prolongation operators. Numerical examples clearly indicate significant time savings in particular for the MGGB scheme.

  2. Method for the Accelerated Testing of the Durability of a Construction Binder using the Arrhenius Approach

    Directory of Open Access Journals (Sweden)

    Fridrichová Marcela

    2016-03-01

    Full Text Available The single most reliable indicator of a material’s durability is its performance in long-term tests, which cannot always be carried out due to a limited time budget. The second option is to perform some kind of accelerated durability tests. The aim of the work described in this article was to develop a method for the accelerated durability testing of binders. It was decided that the Arrhenius equation approach and the theory of chemical reaction kinetics would be applied in this case. The degradation process has been simplified to a single quantifiable parameter, which became compressive strength. A model hydraulic binder based on fluidised bed combustion ash (FBC ash was chosen as the test subject for the development of the method. The model binder and its hydration products were tested by high-temperature X-ray diffraction analysis. The main hydration product of this binder was ettringite. Due to the thermodynamic instability of this mineral, it was possible to verify the proposed method via long term testing. In order to accelerate the chemical reactions in the binder, four combinations of two temperatures (65 and 85°C and two different relative humidities (14 and 100% were used. The upper temperature limit was chosen because of the results of the high-temperature x-ray testing of the ettringite’s decomposition. The calculation formulae for the accelerated durability tests were derived on the basis of data regarding the decrease in compressive strength under the conditions imposed by the four above-mentioned combinations. The mineralogical composition of the binder after degradation was also described. The final degradation product was gypsum under dry conditions and monosulphate under wet conditions. The validity of the method and formula was subsequently verified by means of long-term testing. A very good correspondence between the calculated and real values was achieved. The deviation of these values did not exceed 5 %. The designed

  3. Preliminary determination of Newtonian gravitational constant with angular acceleration feedback method.

    Science.gov (United States)

    Xue, Chao; Quan, Li-Di; Yang, Shan-Qing; Wang, Bing-Peng; Wu, Jun-Fei; Shao, Cheng-Gang; Tu, Liang-Cheng; Milyukov, Vadim; Luo, Jun

    2014-10-13

    This paper describes the preliminary measurement of the Newtonian gravitational constant G with the angular acceleration feedback method at HUST. The apparatus has been built, and preliminary measurement performed, to test all aspects of the experimental design, particularly the feedback function, which was recently discussed in detail by Quan et al. The experimental results show that the residual twist angle of the torsion pendulum at the signal frequency introduces 0.4 ppm to the value of G. The relative uncertainty of the angular acceleration of the turntable is approximately 100 ppm, which is mainly limited by the stability of the apparatus. Therefore, the experiment has been modified with three features: (i) the height of the apparatus is reduced almost by half, (ii) the aluminium shelves were replaced with shelves made from ultra-low expansion material and (iii) a perfect compensation of the laboratory-fixed gravitational background will be carried out. With these improvements, the angular acceleration is expected to be determined with an uncertainty of better than 10 ppm, and a reliable value of G with 20 ppm or below will be obtained in the near future. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  4. Accelerated molecular dynamics and equation-free methods for simulating diffusion in solids.

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jie; Zimmerman, Jonathan A.; Thompson, Aidan Patrick; Brown, William Michael (Oak Ridge National Laboratories, Oak Ridge, TN); Plimpton, Steven James; Zhou, Xiao Wang; Wagner, Gregory John; Erickson, Lindsay Crowl

    2011-09-01

    Many of the most important and hardest-to-solve problems related to the synthesis, performance, and aging of materials involve diffusion through the material or along surfaces and interfaces. These diffusion processes are driven by motions at the atomic scale, but traditional atomistic simulation methods such as molecular dynamics are limited to very short timescales on the order of the atomic vibration period (less than a picosecond), while macroscale diffusion takes place over timescales many orders of magnitude larger. We have completed an LDRD project with the goal of developing and implementing new simulation tools to overcome this timescale problem. In particular, we have focused on two main classes of methods: accelerated molecular dynamics methods that seek to extend the timescale attainable in atomistic simulations, and so-called 'equation-free' methods that combine a fine scale atomistic description of a system with a slower, coarse scale description in order to project the system forward over long times.

  5. Probability-neighbor method of accelerating geometry treatment in reactor Monte Carlo code RMC

    International Nuclear Information System (INIS)

    She, Ding; Li, Zeguang; Xu, Qi; Wang, Kan; Yu, Ganglin

    2011-01-01

    Probability neighbor method (PNM) is proposed in this paper to accelerate geometry treatment of Monte Carlo (MC) simulation and validated in self-developed reactor Monte Carlo code RMC. During MC simulation by either ray-tracking or delta-tracking method, large amounts of time are spent in finding out which cell one particle is located in. The traditional way is to search cells one by one with certain sequence defined previously. However, this procedure becomes very time-consuming when the system contains a large number of cells. Considering that particles have different probability to enter different cells, PNM method optimizes the searching sequence, i.e., the cells with larger probability are searched preferentially. The PNM method is implemented in RMC code and the numerical results show that the considerable time of geometry treatment in MC calculation for complicated systems is saved, especially effective in delta-tracking simulation. (author)

  6. A new method for fluid input into a hybrid synthetic jet actuator

    Directory of Open Access Journals (Sweden)

    Kordík J.

    2014-03-01

    Full Text Available A new principle of flow rectification for hybrid synthetic jet actuators is introduced in this paper. As is well known, the flow rectification can be best accomplished by means of fluidic diodes. Novelty of the present study are fluidic diodes with two mutually opposed nozzles. Interaction between the periodic jet flows from the nozzles causes a difference between the blowing and suction strokes, resulting in a particularly efficient rectification effect. The distance between the nozzle exits as well as the oscillation frequency were the parameters, which were varied during hot-wire measurements. The combination of those parameters achieving the highest volumetric effciency was identified.

  7. Detection methods of pulsed X-rays for transmission tomography with a linear accelerator

    International Nuclear Information System (INIS)

    Glasser, F.

    1988-07-01

    Appropriate detection methods are studied for the development of a high energy tomograph using a linear accelerator for nondestructive testing of bulky objects. The aim is the selection of detectors adapted to a pulsed X-ray source and with a good behavior under X-ray radiations of several MeV. Performance of semiconductors (HgI 2 , Cl doped CdTe, GaAs, Bi 12 Ge0 20 ) and a scintillator (Bi 4 Ge 3 0 12 ) are examined. A prototype tomograph gave images that show the validity of detectors for analysis of medium size equipment such as a concrete drum of 60 cm in diameter [fr

  8. One accelerated method for predicting thermal annealing effects in post-irradiation CMOS devices

    International Nuclear Information System (INIS)

    He Baoping; Zhou Heqin; Guo Hongxia; Luo Yinhong; Zhang Fengqi; Yao Zhibin

    2005-01-01

    A method for accelerated predictions of the long-term anneal effects was presented. In order to find the correspondence between two anneals time, our estimating conditions were that each isochronal step was equal to the duration of the isothermal anneal leading to the same level of charge detrapping. The long term isothermal behavior at 100 degree C and 24 degree C of the type CC4007 CMOS devices were predicted by using isochronal anneal data of 25-250 degree C and compared with an experimental isothermal. The authors note a good agreement between simulation and experiment. (authors)

  9. Practical method and device for enhancing pulse contrast ratio for lasers and electron accelerators

    Science.gov (United States)

    Zhang, Shukui; Wilson, Guy

    2014-09-23

    An apparatus and method for enhancing pulse contrast ratios for drive lasers and electron accelerators. The invention comprises a mechanical dual-shutter system wherein the shutters are placed sequentially in series in a laser beam path. Each shutter of the dual shutter system has an individually operated trigger for opening and closing the shutter. As the triggers are operated individually, the delay between opening and closing first shutter and opening and closing the second shutter is variable providing for variable differential time windows and enhancement of pulse contrast ratio.

  10. Properties of natural and synthetic hydroxyapatite and their surface free energy determined by the thin-layer wicking method

    Science.gov (United States)

    Szcześ, Aleksandra; Yan, Yingdi; Chibowski, Emil; Hołysz, Lucyna; Banach, Marcin

    2018-03-01

    Surface free energy is one of the parameters accompanying interfacial phenomena, occurring also in the biological systems. In this study the thin layer wicking method was used to determine surface free energy and its components for synthetic hydroxyapatite (HA) and natural one obtained from pig bones. The Raman, FTIR and X-Ray photoelectron spectroscopy, X-ray diffraction techniques and thermal analysis showed that both samples consist of carbonated hydroxyapatite without any organic components. Surface free energy and its apolar and polar components were found to be similar for both investigated samples and equalled γSTOT = 52.4 mJ/m2, γSLW = 40.2 mJ/m2 and γSAB = 12.3 mJ/m2 for the synthetic HA and γSTOT = 54.6 mJ/m2, γSLW = 40.3 mJ/m2 and γSAB = 14.3 mJ/m2 for the natural one. Both HA samples had different electron acceptor (γs+) and electron donor (γs-) parameters. The higher value of the electron acceptor was found for the natural HA whereas the electron donor one was higher for the synthetic HA.

  11. Beam transient analyses of Accelerator Driven Subcritical Reactors based on neutron transport method

    Energy Technology Data Exchange (ETDEWEB)

    He, Mingtao; Wu, Hongchun [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Zheng, Youqi, E-mail: yqzheng@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Wang, Kunpeng [Nuclear and Radiation Safety Center, PO Box 8088, Beijing 100082 (China); Li, Xunzhao; Zhou, Shengcheng [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China)

    2015-12-15

    Highlights: • A transport-based kinetics code for Accelerator Driven Subcritical Reactors is developed. • The performance of different kinetics methods adapted to the ADSR is investigated. • The impacts of neutronic parameters deteriorating with fuel depletion are investigated. - Abstract: The Accelerator Driven Subcritical Reactor (ADSR) is almost external source dominated since there is no additional reactivity control mechanism in most designs. This paper focuses on beam-induced transients with an in-house developed dynamic analysis code. The performance of different kinetics methods adapted to the ADSR is investigated, including the point kinetics approximation and space–time kinetics methods. Then, the transient responds of beam trip and beam overpower are calculated and analyzed for an ADSR design dedicated for minor actinides transmutation. The impacts of some safety-related neutronics parameters deteriorating with fuel depletion are also investigated. The results show that the power distribution varying with burnup leads to large differences in temperature responds during transients, while the impacts of kinetic parameters and feedback coefficients are not very obvious. Classification: Core physic.

  12. The fingerprint method for characterization of radioactive waste in hadron accelerators

    Science.gov (United States)

    Magistris, M.; Ulrici, L.

    2008-06-01

    Beam losses are responsible for material activation in most of the components of particle accelerators. The activation is caused by several nuclear processes and varies with the irradiation history and the characteristics of the material (namely chemical composition and size). Once at the end of their operational lifetime, these materials require radiological characterization. The radionuclide inventory depends on the particle spectrum, the irradiation history and the chemical composition of the material. As long as these factors are known and the material cross-sections are available, the induced radioactivity can be calculated analytically. However, these factors vary widely among different items of waste and sometimes they are only partially known. The European Laboratory for Particle Physics (CERN, Geneva) has been operating accelerators for high-energy physics for 50 years. Different methods for the evaluation of the radionuclide inventory are currently under investigation at CERN, including the so-called "fingerprint method". This paper provides a mathematical formulation of the fingerprint method highlighting its advantages and limits of validity. The study includes the application to a real case and the validation of the predictions.

  13. Shelf life prediction of canned fried-rice using accelerated shelf life testing (ASLT) arrhenius method

    Science.gov (United States)

    Kurniadi, M.; Bintang, R.; Kusumaningrum, A.; Nursiwi, A.; Nurhikmat, A.; Susanto, A.; Angwar, M.; Triwiyono; Frediansyah, A.

    2017-12-01

    Research on shelf-life prediction of canned fried rice using Accelerated Shelf-life Test (ASLT) of Arrhenius model has been conducted. The aim of this research to predict shelf life of canned-fried rice products. Lethality value of 121°C for 15 and 20 minutes and Total Plate count methods are used to determine time and temperatures of sterilization process.Various storage temperatures of ASLT Arrhenius method were 35, 45 and 55°C during 35days. Rancidity is one of the derivation quality of canned fried rice. In this research, sample of canned fried rice is tested using rancidity value (TBA). TBA value was used as parameter which be measured once a week periodically. The use of can for fried rice without any chemical preservative is one of the advantage of the product, additionaly the use of physicalproperties such as temperature and pressure during its process can extend the shelf life and reduce the microbial contamination. The same research has never done before for fried rice as ready to eat meal. The result showed that the optimum conditions of sterilization process were 121°C,15 minutes with total plate count number of 9,3 × 101 CFU/ml. Lethality value of canned fried rice at 121°C,15 minutes was 3.63 minutes. The calculated Shelf-life of canned fried rice using Accelerated Shelf-life Test (ASLT) of Arrhenius method was 10.3 months.

  14. Quantification of Newly Discovered Anti-Cancer Drug Enzalutamide in Bulk and Synthetic Mixture by Stability Indicating TLC method.

    Science.gov (United States)

    Chhalotiya, Usmangani K; Prajapati, Dharmendra J; Prajapati, Minesh D; Patel, Jalpa U; Desai, Jaineel

    2017-10-27

    Objective A impressionable, discriminatory and precise stability indicating high performance thin layer chromatographic method has been developed and validated for the estimation of of Enzalutamide in bulk and synthetic mixture. Method The method engaged HPTLC aluminium plates pre-coated with silica gel 60F-254 as the stationary phase while the solvent system was ethyl acetate: toluene (4.5:5.5, v/v). The Rf value of enzalutamide was detected to be 0. 39 ± 0. 005 and the densitometric analysis were carried out in absorbance mode at 246 nm. The linear regression analysis data for the calibration plots presented a virtuous linear relationship for enzalutamide over a concentration range of 20 - 1000ng/band. Results The limit of detection and limit of quantification for enzalutamide was found to be 9.05 and 27.43ng/band. Enzalutamide was imperilled to acid and alkali hydrolysis, chemical oxidation, dry heat degradation and photolytic degradation. The degraded product peaks were well resolved from the pure drug peak with substantial difference in their Rf values. Conclusion Stressed samples were assayed using developed TLC technique. Suggested method was validated with respect to linearity, accuracy, precision and robustness. The method was successfully applied to the estimation of enzalutamide in synthetic mixture. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Methods for open innovation on a genome-design platform associating scientific, commercial, and educational communities in synthetic biology.

    Science.gov (United States)

    Toyoda, Tetsuro

    2011-01-01

    Synthetic biology requires both engineering efficiency and compliance with safety guidelines and ethics. Focusing on the rational construction of biological systems based on engineering principles, synthetic biology depends on a genome-design platform to explore the combinations of multiple biological components or BIO bricks for quickly producing innovative devices. This chapter explains the differences among various platform models and details a methodology for promoting open innovation within the scope of the statutory exemption of patent laws. The detailed platform adopts a centralized evaluation model (CEM), computer-aided design (CAD) bricks, and a freemium model. It is also important for the platform to support the legal aspects of copyrights as well as patent and safety guidelines because intellectual work including DNA sequences designed rationally by human intelligence is basically copyrightable. An informational platform with high traceability, transparency, auditability, and security is required for copyright proof, safety compliance, and incentive management for open innovation in synthetic biology. GenoCon, which we have organized and explained here, is a competition-styled, open-innovation method involving worldwide participants from scientific, commercial, and educational communities that aims to improve the designs of genomic sequences that confer a desired function on an organism. Using only a Web browser, a participating contributor proposes a design expressed with CAD bricks that generate a relevant DNA sequence, which is then experimentally and intensively evaluated by the GenoCon organizers. The CAD bricks that comprise programs and databases as a Semantic Web are developed, executed, shared, reused, and well stocked on the secure Semantic Web platform called the Scientists' Networking System or SciNetS/SciNeS, based on which a CEM research center for synthetic biology and open innovation should be established. Copyright © 2011 Elsevier Inc

  16. A Bayesian reliability evaluation method with integrated accelerated degradation testing and field information

    International Nuclear Information System (INIS)

    Wang, Lizhi; Pan, Rong; Li, Xiaoyang; Jiang, Tongmin

    2013-01-01

    Accelerated degradation testing (ADT) is a common approach in reliability prediction, especially for products with high reliability. However, oftentimes the laboratory condition of ADT is different from the field condition; thus, to predict field failure, one need to calibrate the prediction made by using ADT data. In this paper a Bayesian evaluation method is proposed to integrate the ADT data from laboratory with the failure data from field. Calibration factors are introduced to calibrate the difference between the lab and the field conditions so as to predict a product's actual field reliability more accurately. The information fusion and statistical inference procedure are carried out through a Bayesian approach and Markov chain Monte Carlo methods. The proposed method is demonstrated by two examples and the sensitivity analysis to prior distribution assumption

  17. Fast multipole accelerated boundary element method for the Helmholtz equation in acoustic scattering problems

    Science.gov (United States)

    Li, ShanDe; Gao, GuiBing; Huang, QiBai; Liu, WeiQi; Chen, Jun

    2011-08-01

    We apply the fast multipole method (FMM) accelerated boundary element method (BEM) for the three-dimensional (3D) Helmholtz equation, and as a result, large-scale acoustic scattering problems involving 400000 elements are solved efficiently. This is an extension of the fast multipole BEM for two-dimensional (2D) acoustic problems developed by authors recently. Some new improvements are obtained. In this new technique, the improved Burton-Miller formulation is employed to overcome non-uniqueness difficulties in the conventional BEM for exterior acoustic problems. The computational efficiency is further improved by adopting the FMM and the block diagonal preconditioner used in the generalized minimum residual method (GMRES) iterative solver to solve the system matrix equation. Numerical results clearly demonstrate the complete reliability and efficiency of the proposed algorithm. It is potentially useful for solving large-scale engineering acoustic scattering problems.

  18. In-vivo examples of synthetic aperture vector flow imaging

    DEFF Research Database (Denmark)

    Oddershede, Niels; Hansen, Kristoffer Lindskov; Nielsen, Michael Bachmann

    2007-01-01

    are processed, and movies of full vector flow images are generated. This paper presents still frames from different time instances of these movies. The movie from the femoral data tracks the accelerating velocity in the femoral artery during systole and a backwards flow at the end of the systole. A complex flow...... would be needed. Synthetic aperture vector flow imaging could potentially provide this. The purpose of this paper is to test the synthetic aperture vector flow imaging method on challenging in-vivo data. Two synthetic aperture in-vivo data sets are acquired using a commercial linear array transducer...

  19. Dental movement acceleration: Literature review by an alternative scientific evidence method

    Science.gov (United States)

    Camacho, Angela Domínguez; Cujar, Sergio Andres Velásquez

    2014-01-01

    The aim of this study was to analyze the majority of publications using effective methods to speed up orthodontic treatment and determine which publications carry high evidence-based value. The literature published in Pubmed from 1984 to 2013 was reviewed, in addition to well-known reports that were not classified under this database. To facilitate evidence-based decision making, guidelines such as the Consolidation Standards of Reporting Trials, Preferred Reporting items for systematic Reviews and Meta-analyses, and Transparent Reporting of Evaluations with Non-randomized Designs check list were used. The studies were initially divided into three groups: local application of cell mediators, physical stimuli, and techniques that took advantage of the regional acceleration phenomena. The articles were classified according to their level of evidence using an alternative method for orthodontic scientific article classification. 1a: Systematic Reviews (SR) of randomized clinical trials (RCTs), 1b: Individual RCT, 2a: SR of cohort studies, 2b: Individual cohort study, controlled clinical trials and low quality RCT, 3a: SR of case-control studies, 3b: Individual case-control study, low quality cohort study and short time following split mouth designs. 4: Case-series, low quality case-control study and non-systematic review, and 5: Expert opinion. The highest level of evidence for each group was: (1) local application of cell mediators: the highest level of evidence corresponds to a 3B level in Prostaglandins and Vitamin D; (2) physical stimuli: vibratory forces and low level laser irradiation have evidence level 2b, Electrical current is classified as 3b evidence-based level, Pulsed Electromagnetic Field is placed on the 4th level on the evidence scale; and (3) regional acceleration phenomena related techniques: for corticotomy the majority of the reports belong to level 4. Piezocision, dentoalveolar distraction, alveocentesis, monocortical tooth dislocation and ligament

  20. Dental movement acceleration: Literature review by an alternative scientific evidence method.

    Science.gov (United States)

    Camacho, Angela Domínguez; Velásquez Cujar, Sergio Andres

    2014-09-26

    The aim of this study was to analyze the majority of publications using effective methods to speed up orthodontic treatment and determine which publications carry high evidence-based value. The literature published in Pubmed from 1984 to 2013 was reviewed, in addition to well-known reports that were not classified under this database. To facilitate evidence-based decision making, guidelines such as the Consolidation Standards of Reporting Trials, Preferred Reporting items for systematic Reviews and Meta-analyses, and Transparent Reporting of Evaluations with Non-randomized Designs check list were used. The studies were initially divided into three groups: local application of cell mediators, physical stimuli, and techniques that took advantage of the regional acceleration phenomena. The articles were classified according to their level of evidence using an alternative method for orthodontic scientific article classification. 1a: Systematic Reviews (SR) of randomized clinical trials (RCTs), 1b: Individual RCT, 2a: SR of cohort studies, 2b: Individual cohort study, controlled clinical trials and low quality RCT, 3a: SR of case-control studies, 3b: Individual case-control study, low quality cohort study and short time following split mouth designs. 4: Case-series, low quality case-control study and non-systematic review, and 5: Expert opinion. The highest level of evidence for each group was: (1) local application of cell mediators: the highest level of evidence corresponds to a 3B level in Prostaglandins and Vitamin D; (2) physical stimuli: vibratory forces and low level laser irradiation have evidence level 2b, Electrical current is classified as 3b evidence-based level, Pulsed Electromagnetic Field is placed on the 4(th) level on the evidence scale; and (3) regional acceleration phenomena related techniques: for corticotomy the majority of the reports belong to level 4. Piezocision, dentoalveolar distraction, alveocentesis, monocortical tooth dislocation and

  1. Method for In-vivo Synthetic Aperture B-flow Imaging

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2004-01-01

    is continuously available at all places in the image and any kind of echo canceling filter can therefore be used without the usual initialization problems. The B-flow images are then formed by displaying the gray level image after echo canceling. A fast moving scatterer will give a bright echo and slower moving......-pass filters designed by the Remez exchange algorithm, have been used for the B-flow processing. The image is displayed after each set of emissions yielding 375 frames per second. Both the flow in the carotid artery and the jugular vein can be seen along with an indication of the acceleration and spatial...

  2. The Cysteine S-Alkylation Reaction as a Synthetic Method to Covalently Modify Peptide Sequences.

    Science.gov (United States)

    Calce, Enrica; De Luca, Stefania

    2017-01-05

    Synthetic methodologies to chemically modify peptide molecules have long been investigated for their impact in the field of chemical biology. They allow the introduction of biochemical probes useful for studying protein functions, for manipulating peptides with therapeutic potential, and for structure-activity relationship investigations. The commonly used approach was the derivatization of an amino acid side chain. In this regard, the cysteine, for its unique reactivity, has been widely employed as the substrate for such modifications. Herein, we report on methodologies developed to modify the cysteine thiol group through the S-alkylation reaction. Some procedures perform the alkylation of cysteine derivatives, in order to prepare building blocks to be used during the peptide synthesis, whilst some others selectively modify peptide sequences containing a cysteine residue with a free thiol group, both in solution and in the solid phase. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Air oxidation method employed for the disulfide bond formation of natural and synthetic peptides.

    Science.gov (United States)

    Calce, Enrica; Vitale, Rosa Maria; Scaloni, Andrea; Amodeo, Pietro; De Luca, Stefania

    2015-08-01

    Among the available protocols, chemically driven approaches to oxidize cysteine may not be required for molecules that, under the native-like conditions, naturally fold in conformations ensuring an effective pairing of the right disulfide bridge pattern. In this contest, we successfully prepared the distinctin, a natural heterodimeric peptide, and some synthetic cyclic peptides that are inhibitors of the CXCR4 receptor. In the first case, the air oxidation reaction allowed to connect two peptide chains via disulfide bridge, while in the second case allowed the cyclization of rationally designed peptides by an intramolecular disulfide bridge. Computational approaches helped to either drive de-novo design or suggest structural modifications and optimal oxidization protocols for disulfide-containing molecules. They are able to both predict and to rationalize the propensity of molecules to spontaneously fold in suitable conformations to achieve the right disulfide bridges.

  4. Radical-scavenging Activity of Natural Methoxyphenols vs. Synthetic Ones using the Induction Period Method

    Directory of Open Access Journals (Sweden)

    Seiichiro Fujisawa

    2007-02-01

    Full Text Available The radical-scavenging activities of the synthetic antioxidants 2-allyl-4-X-phenol (X=NO2, Cl, Br, OCH3, COCH3, CH3, t-(CH33, C6H5 and 2,4-dimethoxyphenol, and the natural antioxidants eugenol and isoeugenol, were investigated using differential scanning calorimetry (DSC by measuring their anti-1,1-diphenyl-2-picrylhydrazyl (DPPH radical activity and the induction period for polymerization of methyl methacrylate (MMA initiated by thermal decomposition of 2,2'-azobisisobutyronitrile (AIBN and benzoyl peroxide (BPO. 2-Allyl-4-methoxyphenol and 2,4-dimethoxy-phenol scavenged not only oxygen-centered radicals (PhCOO. derived from BPO, but also carbon-centered radicals (R. derived from the AIBN and DPPH radical much more efficiently, in comparison with eugenol and isoeugenol. 2-Allyl-4-methoxyphenol may be useful for its lower prooxidative activity.

  5. Projected Commutator DIIS Method for Accelerating Hybrid Functional Electronic Structure Calculations.

    Science.gov (United States)

    Hu, Wei; Lin, Lin; Yang, Chao

    2017-11-14

    The commutator direct inversion of the iterative subspace (commutator DIIS or C-DIIS) method developed by Pulay is an efficient and the most widely used scheme in quantum chemistry to accelerate the convergence of self-consistent field (SCF) iterations in Hartree-Fock theory and Kohn-Sham density functional theory. The C-DIIS method requires the explicit storage of the density matrix, the Fock matrix, and the commutator matrix. Hence, the method can only be used for systems with a relatively small basis set, such as the Gaussian basis set. We develop a new method that enables the C-DIIS method to be efficiently employed in electronic structure calculations with a large basis set such as planewaves for the first time. The key ingredient is the projection of both the density matrix and the commutator matrix to an auxiliary matrix called the gauge-fixing matrix. The resulting projected commutator-DIIS method (PC-DIIS) only operates on matrices of the same dimension as that consists of Kohn-Sham orbitals. The cost of the method is comparable to that of standard charge mixing schemes used in large basis set calculations. The PC-DIIS method is gauge-invariant, which guarantees that its performance is invariant with respect to any unitary transformation of the Kohn-Sham orbitals. We demonstrate that the PC-DIIS method can be viewed as an extension of an iterative eigensolver for nonlinear problems. We use the PC-DIIS method for accelerating Kohn-Sham density functional theory calculations with hybrid exchange-correlation functionals, and demonstrate its superior performance compared to the commonly used nested two-level SCF iteration procedure. Furthermore, we demonstrate that in the context of ab initio molecular dynamics (MD) simulation with hybrid functionals one can extrapolate the gauge-fixing matrix to achieve the goal of extrapolating the entire density matrix implicitly along the MD trajectory. Numerical results indicate that the new method significantly reduces

  6. Method and apparatus for use in harnessing solar energy to provide initial acceleration and propulsion of devices

    Energy Technology Data Exchange (ETDEWEB)

    Gutsche, G.E.

    1983-09-13

    The present invention relates to a method of providing thrust and added lift to a vehicle by accelerating fluid heated by solar energy. The present invention also relates to apparatus for carrying out the aforementioned method. Accordingly, the present invention relates to a method of providing initial acceleration and propulsion or enhancing the initial acceleration and propulsion of a vehicle in an environment having at least some fluid, the vehicle being of the type having at least one member, at least a portion of which is treated for absorbing solar radiation for heating fluid adjacent the member for use in propelling the vehicle through the environment. By use of direct and/or focused solar radiation, fluid is heated, accelerated and deflected away from a vehicle by natural or forced convection to provide thrust and lift of the vehicle.

  7. Acute Effect of Different Combined Stretching Methods on Acceleration and Speed in Soccer Players

    Directory of Open Access Journals (Sweden)

    Amiri-Khorasani Mohammadtaghi

    2016-04-01

    Full Text Available The purpose of this study was to investigate the acute effect of different stretching methods, during a warm-up, on the acceleration and speed of soccer players. The acceleration performance of 20 collegiate soccer players (body height: 177.25 ± 5.31 cm; body mass: 65.10 ± 5.62 kg; age: 16.85 ± 0.87 years; BMI: 20.70 ± 5.54; experience: 8.46 ± 1.49 years was evaluated after different warm-up procedures, using 10 and 20 m tests. Subjects performed five types of a warm-up: static, dynamic, combined static + dynamic, combined dynamic + static, and no-stretching. Subjects were divided into five groups. Each group performed five different warm-up protocols in five non-consecutive days. The warm-up protocol used for each group was randomly assigned. The protocols consisted of 4 min jogging, a 1 min stretching program (except for the no-stretching protocol, and 2 min rest periods, followed by the 10 and 20 m sprint test, on the same day. The current findings showed significant differences in the 10 and 20 m tests after dynamic stretching compared with static, combined, and no-stretching protocols. There were also significant differences between the combined stretching compared with static and no-stretching protocols. We concluded that soccer players performed better with respect to acceleration and speed, after dynamic and combined stretching, as they were able to produce more force for a faster execution.

  8. FPGA Acceleration of the phylogenetic likelihood function for Bayesian MCMC inference methods

    Directory of Open Access Journals (Sweden)

    Bakos Jason D

    2010-04-01

    Full Text Available Abstract Background Likelihood (ML-based phylogenetic inference has become a popular method for estimating the evolutionary relationships among species based on genomic sequence data. This method is used in applications such as RAxML, GARLI, MrBayes, PAML, and PAUP. The Phylogenetic Likelihood Function (PLF is an important kernel computation for this method. The PLF consists of a loop with no conditional behavior or dependencies between iterations. As such it contains a high potential for exploiting parallelism using micro-architectural techniques. In this paper, we describe a technique for mapping the PLF and supporting logic onto a Field Programmable Gate Array (FPGA-based co-processor. By leveraging the FPGA's on-chip DSP modules and the high-bandwidth local memory attached to the FPGA, the resultant co-processor can accelerate ML-based methods and outperform state-of-the-art multi-core processors. Results We use the MrBayes 3 tool as a framework for designing our co-processor. For large datasets, we estimate that our accelerated MrBayes, if run on a current-generation FPGA, achieves a 10× speedup relative to software running on a state-of-the-art server-class microprocessor. The FPGA-based implementation achieves its performance by deeply pipelining the likelihood computations, performing multiple floating-point operations in parallel, and through a natural log approximation that is chosen specifically to leverage a deeply pipelined custom architecture. Conclusions Heterogeneous computing, which combines general-purpose processors with special-purpose co-processors such as FPGAs and GPUs, is a promising approach for high-performance phylogeny inference as shown by the growing body of literature in this field. FPGAs in particular are well-suited for this task because of their low power consumption as compared to many-core processors and Graphics Processor Units (GPUs 1.

  9. FPGA Acceleration of the phylogenetic likelihood function for Bayesian MCMC inference methods.

    Science.gov (United States)

    Zierke, Stephanie; Bakos, Jason D

    2010-04-12

    Likelihood (ML)-based phylogenetic inference has become a popular method for estimating the evolutionary relationships among species based on genomic sequence data. This method is used in applications such as RAxML, GARLI, MrBayes, PAML, and PAUP. The Phylogenetic Likelihood Function (PLF) is an important kernel computation for this method. The PLF consists of a loop with no conditional behavior or dependencies between iterations. As such it contains a high potential for exploiting parallelism using micro-architectural techniques. In this paper, we describe a technique for mapping the PLF and supporting logic onto a Field Programmable Gate Array (FPGA)-based co-processor. By leveraging the FPGA's on-chip DSP modules and the high-bandwidth local memory attached to the FPGA, the resultant co-processor can accelerate ML-based methods and outperform state-of-the-art multi-core processors. We use the MrBayes 3 tool as a framework for designing our co-processor. For large datasets, we estimate that our accelerated MrBayes, if run on a current-generation FPGA, achieves a 10x speedup relative to software running on a state-of-the-art server-class microprocessor. The FPGA-based implementation achieves its performance by deeply pipelining the likelihood computations, performing multiple floating-point operations in parallel, and through a natural log approximation that is chosen specifically to leverage a deeply pipelined custom architecture. Heterogeneous computing, which combines general-purpose processors with special-purpose co-processors such as FPGAs and GPUs, is a promising approach for high-performance phylogeny inference as shown by the growing body of literature in this field. FPGAs in particular are well-suited for this task because of their low power consumption as compared to many-core processors and Graphics Processor Units (GPUs).

  10. A novel assistive method for rigidity evaluation during deep brain stimulation surgery using acceleration sensors.

    Science.gov (United States)

    Shah, Ashesh; Coste, Jérôme; Lemaire, Jean-Jacques; Schkommodau, Erik; Taub, Ethan; Guzman, Raphael; Derost, Philippe; Hemm, Simone

    2017-09-01

    OBJECTIVE Despite the widespread use of deep brain stimulation (DBS) for movement disorders such as Parkinson's disease (PD), the exact anatomical target responsible for the therapeutic effect is still a subject of research. Intraoperative stimulation tests by experts consist of performing passive movements of the patient's arm or wrist while the amplitude of the stimulation current is increased. At each position, the amplitude that best alleviates rigidity is identified. Intrarater and interrater variations due to the subjective and semiquantitative nature of such evaluations have been reported. The aim of the present study was to evaluate the use of an acceleration sensor attached to the evaluator's wrist to assess the change in rigidity, hypothesizing that such a change will alter the speed of the passive movements. Furthermore, the combined analysis of such quantitative results with anatomy would generate a more reproducible description of the most effective stimulation sites. METHODS To test the reliability of the method, it was applied during postoperative follow-up examinations of 3 patients. To study the feasibility of intraoperative use, it was used during 9 bilateral DBS operations in patients suffering from PD. Changes in rigidity were calculated by extracting relevant outcome measures from the accelerometer data. These values were used to identify rigidity-suppressing stimulation current amplitudes, which were statistically compared with the amplitudes identified by the neurologist. Positions for the chronic DBS lead implantation that would have been chosen based on the acceleration data were compared with clinical choices. The data were also analyzed with respect to the anatomical location of the stimulating electrode. RESULTS Outcome measures extracted from the accelerometer data were reproducible for the same evaluator, thus providing a reliable assessment of rigidity changes during intraoperative stimulation tests. Of the 188 stimulation sites

  11. The Accelerated Intake: A Method for Increasing Initial Attendance to Outpatient Cocaine Treatment.

    Science.gov (United States)

    Festinger, David S.; And Others

    1996-01-01

    The effectiveness of offering same day appointments at an outpatient cocaine treatment program to increase intake attendance was examined. Seventy-eight clients were given standard or accelerated intake appointments. Significantly more clients who were given accelerated appointments attended the program. An accelerated intake procedure appears to…

  12. Development of synthetic velocity - depth damage curves using a Weighted Monte Carlo method and Logistic Regression analysis

    Science.gov (United States)

    Vozinaki, Anthi Eirini K.; Karatzas, George P.; Sibetheros, Ioannis A.; Varouchakis, Emmanouil A.

    2014-05-01

    Damage curves are the most significant component of the flood loss estimation models. Their development is quite complex. Two types of damage curves exist, historical and synthetic curves. Historical curves are developed from historical loss data from actual flood events. However, due to the scarcity of historical data, synthetic damage curves can be alternatively developed. Synthetic curves rely on the analysis of expected damage under certain hypothetical flooding conditions. A synthetic approach was developed and presented in this work for the development of damage curves, which are subsequently used as the basic input to a flood loss estimation model. A questionnaire-based survey took place among practicing and research agronomists, in order to generate rural loss data based on the responders' loss estimates, for several flood condition scenarios. In addition, a similar questionnaire-based survey took place among building experts, i.e. civil engineers and architects, in order to generate loss data for the urban sector. By answering the questionnaire, the experts were in essence expressing their opinion on how damage to various crop types or building types is related to a range of values of flood inundation parameters, such as floodwater depth and velocity. However, the loss data compiled from the completed questionnaires were not sufficient for the construction of workable damage curves; to overcome this problem, a Weighted Monte Carlo method was implemented, in order to generate extra synthetic datasets with statistical properties identical to those of the questionnaire-based data. The data generated by the Weighted Monte Carlo method were processed via Logistic Regression techniques in order to develop accurate logistic damage curves for the rural and the urban sectors. A Python-based code was developed, which combines the Weighted Monte Carlo method and the Logistic Regression analysis into a single code (WMCLR Python code). Each WMCLR code execution

  13. Use of the backslopping method for accelerated and nutritionally enriched idli fermentation.

    Science.gov (United States)

    Shrivastava, Neha; Ananthanarayan, Laxmi

    2015-08-15

    Idli is a cereal-legume-based fermented food, widely consumed in India. It is popular for its nutritional content, sour taste and appetising aroma. The fermentation time of idli batter varies from 12 to 14 h. A reduction in fermentation time of idli batter is of great significance for large-scale idli production units since it will reduce the batch time and will lead to a greater output. Accelerated fermentation can be potentially achieved by using the backslopping method. The inoculum for backslopping was optimally fermented (12 h) idli batter, dried at room temperature. Backslopping reduced the fermentation time of idli batter from the conventional 12 h to 3 h while successfully maintaining sensory attributes of the product. In the idlis prepared by backslopped expedited batter, thiamine was found to be 50% higher; while reduction of anti-nutrients phytate (11%) and trypsin inhibitor (16%) was higher than the conventionally fermented (12 h) idli batter. Backslopping not only accelerated idli batter fermentation but also enhanced its nutritional value. A similar process can be designed for other fermented foods, to expedite fermentation thus reducing the time requirement. © 2014 Society of Chemical Industry.

  14. Method and device for monochromatization of the internal accelerated particles beam in isochronous cyclotrons

    International Nuclear Information System (INIS)

    Enchevich, I.B.; Dinev, D.H.

    1988-01-01

    The invention assures a reduced size of the supplementary electrode which leads to economy of a material and a more effective use of the accelerator space, where the elements of an axial injection system of the cyclotron particles can be situated. The amplitude homogeneity of the supplementary accelerating field is also improved. To the main high-frequency field, covering the whole scope of the acceleration radiuses, an additional accelerating high-frequency field is introduced comprising a part of the scope of the acceleration radiuses. The frequency of this additional accelerating high frequency field is a third harmonics of the main field frequency. The device consists of a supplementary accelerating electrode, connected to an additional resonator and an additional exciting high-frequency generator. 2 cls., 7 figs

  15. Introducing an attractive method for total biomimetic creation of a synthetic biodegradable bioactive bone scaffold based on statistical experimental design.

    Science.gov (United States)

    Shahbazi, Sara; Zamanian, Ali; Pazouki, Mohammad; Jafari, Yaser

    2018-05-01

    A new total biomimetic technique based on both the water uptake and degradation processes is introduced in this study to provide an interesting procedure to fabricate a bioactive and biodegradable synthetic scaffold, which has a good mechanical and structural properties. The optimization of effective parameters to scaffold fabrication was done by response surface methodology/central composite design (CCD). With this method, a synthetic scaffold was fabricated which has a uniform and open-interconnected porous structure with the largest pore size of 100-200μm. The obtained compressive ultimate strength of ~35MPa and compression modulus of 58MPa are similar to some of the trabecular bone. The pore morphology, size, and distribution of the scaffold were characterized using a scanning electron microscope and mercury porosimeter. Fourier transform infrared spectroscopy, EDAX and X-ray diffraction analyses were used to determine the chemical composition, Ca/P element ratio of mineralized microparticles, and the crystal structure of the scaffolds, respectively. The optimum biodegradable synthetic scaffold based on its raw materials of polypropylene fumarate, hydroxyethyl methacrylate and nano bioactive glass (PPF/HEMA/nanoBG) as 70/30wt/wt%, 20wt%, and 1.5wt/wt% (PHB.732/1.5) with desired porosity, pore size, and geometry were created by 4weeks immersion in SBF. This scaffold showed considerable biocompatibility in the ranging from 86 to 101% for the indirect and direct contact tests and good osteoblast cell attachment when studied with the bone-like cells. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Shelf Life Prediction for Canned Gudeg using Accelerated Shelf Life Testing (ASLT) Based on Arrhenius Method

    Science.gov (United States)

    Nurhayati, R.; Rahayu NH, E.; Susanto, A.; Khasanah, Y.

    2017-04-01

    Gudeg is traditional food from Yogyakarta. It is consist of jackfruit, chicken, egg and coconut milk. Gudeg generally have a short shelf life. Canning or commercial sterilization is one way to extend the shelf life of gudeg. This aims of this research is to predict the shelf life of Andrawinaloka canned gudeg with Accelerated Shelf Life Test methods, Arrhenius model. Canned gudeg stored at three different temperature, there are 37, 50 and 60°C for two months. Measuring the number of Thio Barbituric Acid (TBA), as a critical aspect, were tested every 7 days. Arrhenius model approach is done with the equation order 0 and order 1. The analysis showed that the equation of order 0 can be used as an approach to estimating the shelf life of canned gudeg. The storage of Andrawinaloka canned gudeg at 30°C is predicted untill 21 months and 24 months for 25°C.

  17. Accelerated, microwave-assisted, and conventional solvent extraction methods affect anthocyanin composition from colored grains.

    Science.gov (United States)

    Abdel-Aal, El-Sayed M; Akhtar, Humayoun; Rabalski, Iwona; Bryan, Michael

    2014-02-01

    Anthocyanins are important dietary components with diverse positive functions in human health. This study investigates effects of accelerated solvent extraction (ASE) and microwave-assisted extraction (MAE) on anthocyanin composition and extraction efficiency from blue wheat, purple corn, and black rice in comparison with the commonly used solvent extraction (CSE). Factorial experimental design was employed to study effects of ASE and MAE variables, and anthocyanin extracts were analyzed by spectrophotometry, high-performance liquid chromatography-diode array detector (DAD), and liquid chromatography-mass spectrometry chromatography. The extraction efficiency of ASE and MAE was comparable with CSE at the optimal conditions. The greatest extraction by ASE was achieved at 50 °C, 2500 psi, 10 min using 5 cycles, and 100% flush. For MAE, a combination of 70 °C, 300 W, and 10 min in MAE was the most effective in extracting anthocyanins from blue wheat and purple corn compared with 50 °C, 1200 W, and 20 min for black rice. The anthocyanin composition of grain extracts was influenced by the extraction method. The ASE extraction method seems to be more appropriate in extracting anthocyanins from the colored grains as being comparable with the CSE method based on changes in anthocyanin composition. The method caused lower structural changes in anthocaynins compared with the MAE method. Changes in blue wheat anthocyanins were lower in comparison with purple corn or black rice perhaps due to the absence of acylated anthocyanin compounds in blue wheat. The results show significant differences in anthocyanins among the 3 extraction methods, which indicate a need to standardize a method for valid comparisons among studies and for quality assurance purposes. © 2014 Her Majesty the Queen in Right of Canada Journal of Food Science © 2014 Institute of Food Technologists® Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada.

  18. Electrostatic accelerators

    CERN Document Server

    Hinterberger, F

    2006-01-01

    The principle of electrostatic accelerators is presented. We consider Cockcroft– Walton, Van de Graaff and Tandem Van de Graaff accelerators. We resume high voltage generators such as cascade generators, Van de Graaff band generators, Pelletron generators, Laddertron generators and Dynamitron generators. The speci c features of accelerating tubes, ion optics and methods of voltage stabilization are described. We discuss the characteristic beam properties and the variety of possible beams. We sketch possible applications and the progress in the development of electrostatic accelerators.

  19. COMPUTER AIDED TOLERANCING BASED ON ANALYSIS AND SYNTHETIZES OF TOLERANCES METHOD

    OpenAIRE

    Hassani, Abdessalem; Aifaoui, Nizar; Benamara, Abdelmajid; Samper, Serge

    2008-01-01

    International audience; The tolerancing step has a great importance in the design process. It characterises the relationship between the different sectors of the product life cycle: Design, Manufacturing and Control. We can distinguish several methods to assist the tolerancing process in the design. Based on arithmetic and statistical method, this paper presents a new approach of analysis and verification of tolerances. The chosen approach is based on the Worst Case Method as an arithmetic me...

  20. An ultrasonic-accelerated oxidation method for determining the oxidative stability of biodiesel.

    Science.gov (United States)

    Avila Orozco, Francisco D; Sousa, Antonio C; Domini, Claudia E; Ugulino Araujo, Mario Cesar; Fernández Band, Beatriz S

    2013-05-01

    Biodiesel is considered an alternative energy because it is produced from fats and vegetable oils by means of transesterification. Furthermore, it consists of fatty acid alkyl esters (FAAS) which have a great influence on biodiesel fuel properties and in the storage lifetime of biodiesel itself. The biodiesel storage stability is directly related to the oxidative stability parameter (Induction Time - IT) which is determined by means of the Rancimat® method. This method uses condutimetric monitoring and induces the degradation of FAAS by heating the sample at a constant temperature. The European Committee for Standardization established a standard (EN 14214) to determine the oxidative stability of biodiesel, which requires it to reach a minimum induction period of 6h as tested by Rancimat® method at 110°C. In this research, we aimed at developing a fast and simple alternative method to determine the induction time (IT) based on the FAAS ultrasonic-accelerated oxidation. The sonodegradation of biodiesel samples was induced by means of an ultrasonic homogenizer fitted with an immersible horn at 480Watts of power and 20 duty cycles. The UV-Vis spectrometry was used to monitor the FAAS sonodegradation by measuring the absorbance at 270nm every 2. Biodiesel samples from different feedstock were studied in this work. In all cases, IT was established as the inflection point of the absorbance versus time curve. The induction time values of all biodiesel samples determined using the proposed method was in accordance with those measured through the Rancimat® reference method by showing a R(2)=0.998. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Kernel based methods for accelerated failure time model with ultra-high dimensional data

    Directory of Open Access Journals (Sweden)

    Jiang Feng

    2010-12-01

    Full Text Available Abstract Background Most genomic data have ultra-high dimensions with more than 10,000 genes (probes. Regularization methods with L1 and Lp penalty have been extensively studied in survival analysis with high-dimensional genomic data. However, when the sample size n ≪ m (the number of genes, directly identifying a small subset of genes from ultra-high (m > 10, 000 dimensional data is time-consuming and not computationally efficient. In current microarray analysis, what people really do is select a couple of thousands (or hundreds of genes using univariate analysis or statistical tests, and then apply the LASSO-type penalty to further reduce the number of disease associated genes. This two-step procedure may introduce bias and inaccuracy and lead us to miss biologically important genes. Results The accelerated failure time (AFT model is a linear regression model and a useful alternative to the Cox model for survival analysis. In this paper, we propose a nonlinear kernel based AFT model and an efficient variable selection method with adaptive kernel ridge regression. Our proposed variable selection method is based on the kernel matrix and dual problem with a much smaller n × n matrix. It is very efficient when the number of unknown variables (genes is much larger than the number of samples. Moreover, the primal variables are explicitly updated and the sparsity in the solution is exploited. Conclusions Our proposed methods can simultaneously identify survival associated prognostic factors and predict survival outcomes with ultra-high dimensional genomic data. We have demonstrated the performance of our methods with both simulation and real data. The proposed method performs superbly with limited computational studies.

  2. Optical Flow of Small Objects Using Wavelets, Bootstrap Methods, and Synthetic Discriminant Filters

    National Research Council Canada - National Science Library

    Hewer, Gary

    1997-01-01

    ...) targets in highly cluttered and noisy environments. In this paper; we present a novel wavelet detection algorithm which incorporates adaptive CFAR detection statistics using the bootstrap method...

  3. Development of an accelerated leaching method for incineration bottom ash correlated to toxicity characteristic leaching protocol.

    Science.gov (United States)

    Lin, Shengxuan; Zhou, Xuedong; Ge, Liya; Ng, Sum Huan; Zhou, Xiaodong; Chang, Victor Wei-Chung

    2016-10-01

    Heavy metals and some metalloids are the most significant inorganic contaminants specified in toxicity characteristic leaching procedure (TCLP) in determining the safety of landfills or further utilization. As a consequence, a great deal of efforts had been made on the development of miniaturized analytical devices, such as Microchip Electrophoresis (ME) and μTAS for on-site testing of heavy metals and metalloids to prevent spreading of those pollutants or decrease the reutilization period of waste materials such as incineration bottom ash. However, the bottleneck lied in the long and tedious conventional TCLP that requires 18 h of leaching. Without accelerating the TCLP process, the on-site testing of the waste material leachates was impossible. In this study, therefore, a new accelerated leaching method (ALM) combining ultrasonic assisted leaching with tumbling was developed to reduce the total leaching time from 18 h to 30 min. After leaching, the concentrations of heavy metals and metalloids were determined with ICP-MS or ICP-optical emission spectroscopy. No statistical significance between ALM and TCLP was observed for most heavy metals (i.e., cobalt, manganese, mercury, molybdenum, nickel, silver, strontium, and tin) and metalloids (i.e., arsenic and selenium). For the heavy metals with statistical significance, correlation factors derived between ALM and TCLP were 0.56, 0.20, 0.037, and 0.019 for barium, cadmium, chromium, and lead, respectively. Combined with appropriate analytical techniques (e.g., ME), the ALM can be applied to rapidly prepare the incineration bottom ash samples as well as other environmental samples for on-site determination of heavy metals and metalloids. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Applicability of an innovative steroid-profiling method to determine synthetic growth promoter abuse in cattle

    NARCIS (Netherlands)

    Blokland, M.H.; Tricht, van E.F.; Ginkel, van L.A.; Sterk, S.S.

    2017-01-01

    A robust LC–MS/MS method was developed to quantify a large number of phase I and phase II steroids in urine. The decision limit is for most compounds lower than 1 ng ml−1 with a measurement uncertainty smaller than 30%. The method is fully validated and was applied to assess the influence of

  5. Synthetic Study of 2.5-D ATEM Based on Finite Element Method

    DEFF Research Database (Denmark)

    Qiang, Jianke; Zhou, Junjie; Cai, Hongzhu

    2013-01-01

    Based on the regular triangular dissection for finite element method, we implemented the forward modeling of 2.5-D airborne transient electromagnetic method. The 3-D EM field was firstly transformed into Laplace domain and after that we will apply Fourier transform to reduce the dimension from 3-D...... to 2.5-D. We can obtain the EM field solution in Laplace domain by applying finite element method. The inverse Laplace transform is applied to our solution which finally leads to the airborne EM response in time domain. In compared to the traditional method, we apply our finite element method...... to the anomalous field which can avoid the singularity problem caused by the source which can excite the anomalous EM field. The EM source can be imposed to our process by incorporate the background EM field. The computation error can be accumulated due to the large variation of EM field and it can also...

  6. Method for detecting moment connection fracture using high-frequency transients in recorded accelerations

    Science.gov (United States)

    Rodgers, J.E.; Elebi, M.

    2011-01-01

    The 1994 Northridge earthquake caused brittle fractures in steel moment frame building connections, despite causing little visible building damage in most cases. Future strong earthquakes are likely to cause similar damage to the many un-retrofitted pre-Northridge buildings in the western US and elsewhere. Without obvious permanent building deformation, costly intrusive inspections are currently the only way to determine if major fracture damage that compromises building safety has occurred. Building instrumentation has the potential to provide engineers and owners with timely information on fracture occurrence. Structural dynamics theory predicts and scale model experiments have demonstrated that sudden, large changes in structure properties caused by moment connection fractures will cause transient dynamic response. A method is proposed for detecting the building-wide level of connection fracture damage, based on observing high-frequency, fracture-induced transient dynamic responses in strong motion accelerograms. High-frequency transients are short (<1 s), sudden-onset waveforms with frequency content above 25 Hz that are visually apparent in recorded accelerations. Strong motion data and damage information from intrusive inspections collected from 24 sparsely instrumented buildings following the 1994 Northridge earthquake are used to evaluate the proposed method. The method's overall success rate for this data set is 67%, but this rate varies significantly with damage level. The method performs reasonably well in detecting significant fracture damage and in identifying cases with no damage, but fails in cases with few fractures. Combining the method with other damage indicators and removing records with excessive noise improves the ability to detect the level of damage. ?? 2010 Elsevier B.V. All rights reserved.

  7. Analytical synthetic methods of solution of neutron transport equation with diffusion theory approaches energy multigroup

    International Nuclear Information System (INIS)

    Moraes, Pedro Gabriel B.; Leite, Michel C.A.; Barros, Ricardo C.

    2013-01-01

    In this work we developed a software to model and generate results in tables and graphs of one-dimensional neutron transport problems in multi-group formulation of energy. The numerical method we use to solve the problem of neutron diffusion is analytic, thus eliminating the truncation errors that appear in classical numerical methods, e.g., the method of finite differences. This numerical analytical method increases the computational efficiency, since they are not refined spatial discretization necessary because for any spatial discretization grids used, the numerical result generated for the same point of the domain remains unchanged unless the rounding errors of computational finite arithmetic. We chose to develop a computational application in MatLab platform for numerical computation and program interface is simple and easy with knobs. We consider important to model this neutron transport problem with a fixed source in the context of shielding calculations of radiation that protects the biosphere, and could be sensitive to ionizing radiation

  8. A study on synthetic method and material characteristics of magnesium ammine chloride as ammonia transport materials for solid SCR

    International Nuclear Information System (INIS)

    Shin, Jong Kook; Yoon, Cheon Seog; Kim, Hong Suk

    2015-01-01

    Among various ammonium salts and metal ammine chlorides used as solid materials for the sources of ammonia with solid SCR for lean NOx reduction, magnesium ammine chloride was taken up for study in this paper because of its ease of handling and safety. Lab-scale synthetic method of magnesium ammine chloride were studied for different durations, temperatures, and pressures with proper ammonia gas charged, as a respect of ammonia gas adsorption rate(%). To understand material characteristics for lab-made magnesium ammine chloride, DA, IC, FT-IR, XRD and SDT analyses were performed using the published data available in literature. From the analytical results, the water content in the lab-made magnesium ammine chloride can be determined. A new test procedure for water removal was proposed, by which the adsorption rate of lab-made sample was found to be approximately 100%

  9. Synthetic Methods and Exploring Biological Potential of Various Substituted Quinoxalin-2-one Derivatives

    OpenAIRE

    Mohammad Asif

    2016-01-01

    Substituted quinoxaline have considerable interest in chemistry, biology and pharmacology. Quinoxaline derivatives are capable with variety of biological activities and possess different biological activities, of which the most potent are anti-microbial, analgesic and anti-inflammatory activities. It facilitated the researchers to develop various methods for their synthesis and their applications. In this review represented different methods of synthesis, reactivity and various biological act...

  10. Hydrogen production methods efficiency coupled to an advanced high temperature accelerator driven system

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, Daniel González; Lira, Carlos Alberto Brayner de Oliveira [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear; Fernández, Carlos García, E-mail: danielgonro@gmail.com, E-mail: mmhamada@ipen.br [Instituto Superior de Tecnologías y Ciencias aplicadas (InSTEC), La Habana (Cuba)

    2017-07-01

    The hydrogen economy is one of the most promising concepts for the energy future. In this scenario, oil is replaced by hydrogen as an energy carrier. This hydrogen, rather than oil, must be produced in volumes not provided by the currently employed methods. In this work two high temperature hydrogen production methods coupled to an advanced nuclear system are presented. A new design of a pebbled-bed accelerator nuclear driven system called TADSEA is chosen because of the advantages it has in matters of transmutation and safety. For the conceptual design of the high temperature electrolysis process a detailed computational fluid dynamics model was developed to analyze the solid oxide electrolytic cell that has a huge influence on the process efficiency. A detailed flowsheet of the high temperature electrolysis process coupled to TADSEA through a Brayton gas cycle was developed using chemical process simulation software: Aspen HYSYS®. The model with optimized operating conditions produces 0.1627 kg/s of hydrogen, resulting in an overall process efficiency of 34.51%, a value in the range of results reported by other authors. A conceptual design of the iodine-sulfur thermochemical water splitting cycle was also developed. The overall efficiency of the process was calculated performing an energy balance resulting in 22.56%. The values of efficiency, hydrogen production rate and energy consumption of the proposed models are in the values considered acceptable in the hydrogen economy concept, being also compatible with the TADSEA design parameters. (author)

  11. Hydrogen production methods efficiency coupled to an advanced high temperature accelerator driven system

    International Nuclear Information System (INIS)

    Rodríguez, Daniel González; Lira, Carlos Alberto Brayner de Oliveira

    2017-01-01

    The hydrogen economy is one of the most promising concepts for the energy future. In this scenario, oil is replaced by hydrogen as an energy carrier. This hydrogen, rather than oil, must be produced in volumes not provided by the currently employed methods. In this work two high temperature hydrogen production methods coupled to an advanced nuclear system are presented. A new design of a pebbled-bed accelerator nuclear driven system called TADSEA is chosen because of the advantages it has in matters of transmutation and safety. For the conceptual design of the high temperature electrolysis process a detailed computational fluid dynamics model was developed to analyze the solid oxide electrolytic cell that has a huge influence on the process efficiency. A detailed flowsheet of the high temperature electrolysis process coupled to TADSEA through a Brayton gas cycle was developed using chemical process simulation software: Aspen HYSYS®. The model with optimized operating conditions produces 0.1627 kg/s of hydrogen, resulting in an overall process efficiency of 34.51%, a value in the range of results reported by other authors. A conceptual design of the iodine-sulfur thermochemical water splitting cycle was also developed. The overall efficiency of the process was calculated performing an energy balance resulting in 22.56%. The values of efficiency, hydrogen production rate and energy consumption of the proposed models are in the values considered acceptable in the hydrogen economy concept, being also compatible with the TADSEA design parameters. (author)

  12. Accelerated iterative Methods of PET image reconstruction using ordered subsets technology

    International Nuclear Information System (INIS)

    Liu Li; Yin Yin

    2004-01-01

    Purpose: Positron Emission Tomography (PET) is one of the most advanced medical imaging techniques in the world. The traditional practical image reconstruction algorithm of PET is Filtered- Backproiecfion (FBP). The iterative Methods based on statistical model and Least- Square principle were usually used in research stage, for their slow convergent speeds. Recently a new approach-- Ordered Subsets Expectation Maximization (OS-EM) has been used in clinic nuclear tomography, which can greatly reduce the computing time while maintaining the better' spatial resolution of the well-known Maximum Likelihood Expectation Maximization (ML-EM)iterative reconstruction method. The advantage of OS-EM over ML-EM is due to the usage of' the Ordered Subsets technology (OS), which provides a speedup factor of about L (the number of subsets). In principle, OS technology can be used in all iterative image algorithms. In our work, the Ordered Subsets Least Square (OS-LS) was introduced, and the reconstructed results were compared with OS-EM both by simulated data and real PET data. Methods: 64 x 64 Jaszczak-like model was constructed, with maximum 70 and minimum 10, see Fig l(a), 64-bin by 32-angle sinogram was simulated. And the real PET transmission sonogram data (160*192 in size) of a thorax phantom was also used to demonstrate the accelerating effect of OS in OS-EM and OS-LS. When the number of subset L equals to 1, OS-EM and OS-LS reduce to the traditional ML-EM and LS respectively. Results: The reconstructed images by 1 iteration OS-EM and OS-LS are shown in Fig1(b-e) with From Fig 1, we see the accelerating effect of OS is obvious both in OS-EM and OS-LS, and the image reconstructed by OS-EM is still better than that of OS-LS with less noise. The image reconstructed by OS-EM is still better than that of OS-LS with less noise Fig 2 shows the reconstructed images of a thorax phantom (128*128 in size) by OS-EM and OS-LS, of a real PET transmission sinogram, which was the

  13. LC/ESI-MS/MS method for quantification of 28 synthetic cannabinoids in neat oral fluid and its application to preliminary studies on their detection windows.

    Science.gov (United States)

    Kneisel, Stefan; Speck, Michael; Moosmann, Bjoern; Corneillie, Todd M; Butlin, Nathaniel G; Auwärter, Volker

    2013-05-01

    Serum and urine samples are commonly used for the analysis of synthetic cannabinoids in biofluids; however, their utilization as analytical matrices for drug abstinence control features some substantial drawbacks. While for blood collection invasive sampling is inevitable, the urinary analysis of synthetic cannabinoids is limited by the lack of available reference standards of the respective major metabolites. Moreover, the long detectability of synthetic cannabinoids in both matrices hampers the identification of a recent synthetic cannabinoid use. This article describes the development, validation and application of an LC/ESI-MS/MS method for the quantification of 28 synthetic cannabinoids in neat oral fluid (OF) samples. OF samples were prepared by protein precipitation using ice-cold acetonitrile. Chromatographic separation was achieved by gradient elution on a Luna Phenyl Hexyl column (50 × 2 mm, 5 μm), while detection was carried out on a QTrap 4000 instrument in positive ionization mode. The limits of detection ranged from 0.02 to 0.40 ng/mL, whereas the lower limits of quantification ranged from 0.2 to 4.0 ng/mL. The method was applied to authentic samples collected during two preliminary studies in order to obtain insights into the general detectability and detection windows of synthetic cannabinoids in this matrix. The results indicate that synthetic cannabinoids are transferred from the blood stream into OF and vice versa only at a very low rate. Therefore, positive OF samples are due to contamination of the oral cavity during smoking. As these drug-contaminations could be detected up to approximately 2 days, neat oral fluid appears to be well suited for detection of a recent synthetic cannabinoid use.

  14. Hybrid Monte Carlo/Deterministic Methods for Accelerating Active Interrogation Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Peplow, Douglas E. [ORNL; Miller, Thomas Martin [ORNL; Patton, Bruce W [ORNL; Wagner, John C [ORNL

    2013-01-01

    The potential for smuggling special nuclear material (SNM) into the United States is a major concern to homeland security, so federal agencies are investigating a variety of preventive measures, including detection and interdiction of SNM during transport. One approach for SNM detection, called active interrogation, uses a radiation source, such as a beam of neutrons or photons, to scan cargo containers and detect the products of induced fissions. In realistic cargo transport scenarios, the process of inducing and detecting fissions in SNM is difficult due to the presence of various and potentially thick materials between the radiation source and the SNM, and the practical limitations on radiation source strength and detection capabilities. Therefore, computer simulations are being used, along with experimental measurements, in efforts to design effective active interrogation detection systems. The computer simulations mostly consist of simulating radiation transport from the source to the detector region(s). Although the Monte Carlo method is predominantly used for these simulations, difficulties persist related to calculating statistically meaningful detector responses in practical computing times, thereby limiting their usefulness for design and evaluation of practical active interrogation systems. In previous work, the benefits of hybrid methods that use the results of approximate deterministic transport calculations to accelerate high-fidelity Monte Carlo simulations have been demonstrated for source-detector type problems. In this work, the hybrid methods are applied and evaluated for three example active interrogation problems. Additionally, a new approach is presented that uses multiple goal-based importance functions depending on a particle s relevance to the ultimate goal of the simulation. Results from the examples demonstrate that the application of hybrid methods to active interrogation problems dramatically increases their calculational efficiency.

  15. Effect of the synthetic method on the catalytic activity of alumina: Epoxidation of cyclohexene

    Energy Technology Data Exchange (ETDEWEB)

    Valderruten, N.E., E-mail: nevalderruten@icesi.edu.co [Departamento de Ciencias Químicas, Universidad Icesi, Cali (Colombia); Peña, W.F.; Ramírez, A.E. [Departamento de Química, Universidad del Cauca, Popayán (Colombia); Rodríguez-Páez, J.E. [Departamento de Física, Universidad del Cauca, Popayán (Colombia)

    2015-02-15

    Graphical abstract: Temperature influence on percent conversion and selectivity in the epoxidation of cyclohexene using commercial alumina as a catalyst. - Highlights: • Aluminum oxide was synthesized using Pechini method. • The alumina obtained showed a mix of boehmite and γ-alumina phases. • We research an economically feasible method to obtain alumina for use as a catalyst. • Alumina obtained by Pechini showed high percent conversion and/or selectivity. • The best results were 78% conversion and 78% selectivity to epoxidation reactions. - Abstract: Al{sub 2}O{sub 3} was prepared from different inorganic precursors via the Pechini method and compared with Al{sub 2}O{sub 3} prepared by the sol–gel method. Structural characterization of these materials was carried out by FTIR, X-ray diffraction (XRD), N{sub 2} adsorption at −196 °C and transmission electron microscopy (TEM). The solids were tested in the epoxidation of cyclohexene and a difference in their catalytic activities was observed. The characterization results indicate that the samples prepared by Pechini have a mixture of γ-alumina and boehmite, a condition favoring catalytic activity, whereas the sol–gel sample is less crystalline due to higher boehmite content. These results indicate that both the nature of the precursor and the method of synthesis strongly affect the catalytic activity of Al{sub 2}O{sub 3}.

  16. Water-contained surfactant-based vortex-assisted microextraction method combined with liquid chromatography for determination of synthetic antioxidants from edible oil.

    Science.gov (United States)

    Amlashi, Nadiya Ekbatani; Hadjmohammadi, Mohammad Reza; Nazari, Seyed Saman Seyed Jafar

    2014-09-26

    For the first time, a novel water-contained surfactant-based vortex-assisted microextraction method (WSVAME) was developed for the extraction of two synthetic antioxidants (t-butyl hydroquinone (TBHQ) and butylated hydroxyanisole (BHA)) from edible oil samples. The novel microextraction method is based on the injection of an aqueous solution of non-ionic surfactant, Brij-35, into the oil sample in a conical bottom glass tube to form a cloudy solution. Vortex mixing was applied to accelerate the dispersion process. After extraction and phase separation by centrifugation, the lower sediment phase was directly analyzed by HPLC. The effects of the four experimental parameters including volume and concentration of extraction solvent (aqueous solution of Brij-35), percentage of acetic acid added to the oil sample and vortex time on the extraction efficiency were studied with a full factorial design. The central composite design and multiple linear regression method were applied for the construction of the best polynomial model based on experimental recoveries. The proposed method showed good linearity within the range of 0.200-200 μg mL(-1), the square of correlation coefficient higher than 0.999 and appropriate limit of detection (0.026 and 0.020 μg mL(-1) for TBHQ and BHA, respectively), while the precision for inner-day was ≤ 3.0 (n=5) and it was ≤ 3.80 (n=5) for inter-day assay. Under the optimal condition (30 μL of 0.10 mol L(-1) Brij-35 solution as extraction solvent and vortex time 1 min), the method was successfully applied for determination of TBHQ and BHA in different commercial edible oil samples. The recoveries in all cases were above 95%, with relative standard deviations below 5%. This approach is considered as a simple, sensitive and environmentally friendly method because of biodegradability of the extraction phase and no use of organic solvent in the extraction procedure. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. A Novel Ship Detection Method Based on Gradient and Integral Feature for Single-Polarization Synthetic Aperture Radar Imagery

    Directory of Open Access Journals (Sweden)

    Hao Shi

    2018-02-01

    Full Text Available With the rapid development of remote sensing technologies, SAR satellites like China’s Gaofen-3 satellite have more imaging modes and higher resolution. With the availability of high-resolution SAR images, automatic ship target detection has become an important topic in maritime research. In this paper, a novel ship detection method based on gradient and integral features is proposed. This method is mainly composed of three steps. First, in the preprocessing step, a filter is employed to smooth the clutters and the smoothing effect can be adaptive adjusted according to the statistics information of the sub-window. Thus, it can retain details while achieving noise suppression. Second, in the candidate area extraction, a sea-land segmentation method based on gradient enhancement is presented. The integral image method is employed to accelerate computation. Finally, in the ship target identification step, a feature extraction strategy based on Haar-like gradient information and a Radon transform is proposed. This strategy decreases the number of templates found in traditional Haar-like methods. Experiments were performed using Gaofen-3 single-polarization SAR images, and the results showed that the proposed method has high detection accuracy and rapid computational efficiency. In addition, this method has the potential for on-board processing.

  18. A Rapid Synthetic Method for the Preparation of Two Tris-Cobalt(III) Compounds.

    Science.gov (United States)

    Jackman, Donald C.; Rillema, D. Paul

    1989-01-01

    Reports a method of preparation for tris(ethylenediamine)cobalt(III) and tris(2,2'-bipyridine)cobalt(III) that will shorten the preparation time by approximately 3 hours. Notes the time for synthesis and isolation of compound one was 1 hour (yield 38 percent) while compound two took 50 minutes (yield 71%). (MVL)

  19. Method for detecting binding efficiencies of synthetic oligonucleotides: Targeting bacteria and insects

    Science.gov (United States)

    Expanding applications of gene-based targeting biotechnology in functional genomics and the treatment of plants, animals, and microbes has synergized the need for new methods to measure binding efficiencies of these products to their genetic targets. The adaptation and innovative use of Cell–Penetra...

  20. Seismic Hazard Analysis based on Earthquake Vulnerability and Peak Ground Acceleration using Microseismic Method at Universitas Negeri Semarang

    Science.gov (United States)

    Sulistiawan, H.; Supriyadi; Yulianti, I.

    2017-02-01

    Microseismic is a harmonic vibration of land that occurs continuously at a low frequency. The characteristics of microseismic represents the characteristics of the soil layer based on the value of its natural frequency. This paper presents the analysis of seismic hazard at Universitas Negeri Semarang using microseismic method. The data acquisition was done at 20 points with distance between points 300 m by using three component’s seismometer. The data was processed using Horizontal to Vertical Spectral Ratio (HVSR) method to obtain the natural frequency and amplification value. The value of the natural frequency and amplification used to determine the value of the earthquake vulnerability and peak ground acceleration (PGA). The result shows then the earthquake vulnerability value range from 0.2 to 7.5, while the value of the average peak ground acceleration (PGA) is in the range 10-24 gal. Therefore, the average peak ground acceleration equal to earthquake intensity IV MMI scale.

  1. Earthquake acceleration amplification based on single microtremor test

    Science.gov (United States)

    Jaya Syahbana, Arifan; Kurniawan, Rahmat; Soebowo, Eko

    2018-02-01

    Understanding soil dynamics is needed to understand soil behaviour, including the parameters of earthquake acceleration amplification. Many researchers now conduct single microtremor tests to obtain amplification of velocity and natural periods of soil at test sites. However, these amplification parameters are rarely used, so a method is needed to convert the velocity amplification to acceleration amplification. This paper will discuss the proposed process of changing the value of amplification. The proposed method is to integrate the time histories of the synthetic earthquake acceleration of the soil surface under the deaggregation at that location so the time histories of the velocity earthquake will be obtained. Next is to conduct a “fitting curve” between amplification by a single microtremor test with amplification of the synthetic earthquake velocity time histories. After obtaining the fitting curve time histories of velocity, differentiation will be conducted to obtain fitting curve acceleration time histories. The final step after obtaining the fitting curve is to compare the acceleration of the “fitting curve” against the histories time of the acceleration of synthetic earthquake at bedrocks to obtain single microtremor acceleration amplification factor.

  2. Methods and problems in assessing the impacts of accelerated sea-level rise

    Science.gov (United States)

    Nicholls, Robert J.; Dennis, Karen C.; Volonte, Claudio R.; Leatherman, Stephen P.

    1992-06-01

    Accelerated sea-level rise is one of the more certain responses to global warming and presents a major challenge to mankind. However, it is important to note that sea-level rise is only manifest over long timescales (decades to centuries). Coastal scientists are increasingly being called upon to assess the physical, economic and societal impacts of sea-level rise and hence investigate appropriate response strategies. Such assessments are difficult in many developing countries due to a lack of physical, demographic and economic data. In particular, there is a lack of appropriate topographic information for the first (physical) phase of the analysis. To overcome these difficulties we have developed a new rapid and low-cost reconnaissance technique: ``aerial videotape-assisted vulnerability analysis'' (AVA). It involves: 1) videotaping the coastline from a small airplane; 2) limited ground-truth measurements; and 3) archive research. Combining the video record with the ground-truth information characterizes the coastal topography and, with an appropriate land loss model, estimates of the physical impact for different sea-level rise scenarios can be made. However, such land loss estimates raise other important questions such as the appropriate seaward limit of the beach profile. Response options also raise questions such as the long-term costs of seawalls. Therefore, realistic low and high estiimates were developed. To illustrate the method selected results from Senegal, Uruguay and Venezuela are presented.

  3. Accelerated life-test methods and results for implantable electronic devices with adhesive encapsulation.

    Science.gov (United States)

    Huang, Xuechen; Denprasert, Petcharat May; Zhou, Li; Vest, Adriana Nicholson; Kohan, Sam; Loeb, Gerald E

    2017-09-01

    We have developed and applied new methods to estimate the functional life of miniature, implantable, wireless electronic devices that rely on non-hermetic, adhesive encapsulants such as epoxy. A comb pattern board with a high density of interdigitated electrodes (IDE) could be used to detect incipient failure from water vapor condensation. Inductive coupling of an RF magnetic field was used to provide DC bias and to detect deterioration of an encapsulated comb pattern. Diodes in the implant converted part of the received energy into DC bias on the comb pattern. The capacitance of the comb pattern forms a resonant circuit with the inductor by which the implant receives power. Any moisture affects both the resonant frequency and the Q-factor of the resonance of the circuitry, which was detected wirelessly by its effects on the coupling between two orthogonal RF coils placed around the device. Various defects were introduced into the comb pattern devices to demonstrate sensitivity to failures and to correlate these signals with visual inspection of failures. Optimized encapsulation procedures were validated in accelerated life tests of both comb patterns and a functional neuromuscular stimulator under development. Strong adhesive bonding between epoxy and electronic circuitry proved to be necessary and sufficient to predict 1 year packaging reliability of 99.97% for the neuromuscular stimulator.

  4. GPU accelerated simulations of 3D deterministic particle transport using discrete ordinates method

    International Nuclear Information System (INIS)

    Gong Chunye; Liu Jie; Chi Lihua; Huang Haowei; Fang Jingyue; Gong Zhenghu

    2011-01-01

    Graphics Processing Unit (GPU), originally developed for real-time, high-definition 3D graphics in computer games, now provides great faculty in solving scientific applications. The basis of particle transport simulation is the time-dependent, multi-group, inhomogeneous Boltzmann transport equation. The numerical solution to the Boltzmann equation involves the discrete ordinates (S n ) method and the procedure of source iteration. In this paper, we present a GPU accelerated simulation of one energy group time-independent deterministic discrete ordinates particle transport in 3D Cartesian geometry (Sweep3D). The performance of the GPU simulations are reported with the simulations of vacuum boundary condition. The discussion of the relative advantages and disadvantages of the GPU implementation, the simulation on multi GPUs, the programming effort and code portability are also reported. The results show that the overall performance speedup of one NVIDIA Tesla M2050 GPU ranges from 2.56 compared with one Intel Xeon X5670 chip to 8.14 compared with one Intel Core Q6600 chip for no flux fixup. The simulation with flux fixup on one M2050 is 1.23 times faster than on one X5670.

  5. Advocacy for the Archives and History Office of the SLAC National Accelerator Laboratory: Stages and Methods

    Energy Technology Data Exchange (ETDEWEB)

    Deken, Jean Marie; /SLAC

    2009-06-19

    Advocating for the good of the SLAC Archives and History Office (AHO) has not been a one-time affair, nor has it been a one-method procedure. It has required taking time to ascertain the current and perhaps predict the future climate of the Laboratory, and it has required developing and implementing a portfolio of approaches to the goal of building a stronger archive program by strengthening and appropriately expanding its resources. Among the successful tools in the AHO advocacy portfolio, the Archives Program Review Committee has been the most visible. The Committee and the role it serves as well as other formal and informal advocacy efforts are the focus of this case study My remarks today will begin with a brief introduction to advocacy and outreach as I understand them, and with a description of the Archives and History Office's efforts to understand and work within the corporate culture of the SLAC National Accelerator Laboratory. I will then share with you some of the tools we have employed to advocate for the Archives and History Office programs and activities; and finally, I will talk about how well - or badly - those tools have served us over the past decade.

  6. Accelerating what works: using qualitative research methods in developing a change package for a learning collaborative.

    Science.gov (United States)

    Sorensen, Asta V; Bernard, Shulamit L

    2012-02-01

    Learning (quality improvement) collaboratives are effective vehicles for driving coordinated organizational improvements. A central element of a learning collaborative is the change package-a catalogue of strategies, change concepts, and action steps that guide participants in their improvement efforts. Despite a vast literature describing learning collaboratives, little to no information is available on how the guiding strategies, change concepts, and action items are identified and developed to a replicable and actionable format that can be used to make measurable improvements within participating organizations. The process for developing the change package for the Health Resources and Services Administration's (HRSA) Patient Safety and Clinical Pharmacy Services Collaborative entailed environmental scan and identification of leading practices, case studies, interim debriefing meetings, data synthesis, and a technical expert panel meeting. Data synthesis involved end-of-day debriefings, systematic qualitative analyses, and the use of grounded theory and inductive data analysis techniques. This approach allowed systematic identification of innovative patient safety and clinical pharmacy practices that could be adopted in diverse environments. A case study approach enabled the research team to study practices in their natural environments. Use of grounded theory and inductive data analysis techniques enabled identification of strategies, change concepts, and actionable items that might not have been captured using different approaches. Use of systematic processes and qualitative methods in identification and translation of innovative practices can greatly accelerate the diffusion of innovations and practice improvements. This approach is effective whether or not an individual organization is part of a learning collaborative.

  7. GPU accelerated study of heat transfer and fluid flow by lattice Boltzmann method on CUDA

    Science.gov (United States)

    Ren, Qinlong

    Lattice Boltzmann method (LBM) has been developed as a powerful numerical approach to simulate the complex fluid flow and heat transfer phenomena during the past two decades. As a mesoscale method based on the kinetic theory, LBM has several advantages compared with traditional numerical methods such as physical representation of microscopic interactions, dealing with complex geometries and highly parallel nature. Lattice Boltzmann method has been applied to solve various fluid behaviors and heat transfer process like conjugate heat transfer, magnetic and electric field, diffusion and mixing process, chemical reactions, multiphase flow, phase change process, non-isothermal flow in porous medium, microfluidics, fluid-structure interactions in biological system and so on. In addition, as a non-body-conformal grid method, the immersed boundary method (IBM) could be applied to handle the complex or moving geometries in the domain. The immersed boundary method could be coupled with lattice Boltzmann method to study the heat transfer and fluid flow problems. Heat transfer and fluid flow are solved on Euler nodes by LBM while the complex solid geometries are captured by Lagrangian nodes using immersed boundary method. Parallel computing has been a popular topic for many decades to accelerate the computational speed in engineering and scientific fields. Today, almost all the laptop and desktop have central processing units (CPUs) with multiple cores which could be used for parallel computing. However, the cost of CPUs with hundreds of cores is still high which limits its capability of high performance computing on personal computer. Graphic processing units (GPU) is originally used for the computer video cards have been emerged as the most powerful high-performance workstation in recent years. Unlike the CPUs, the cost of GPU with thousands of cores is cheap. For example, the GPU (GeForce GTX TITAN) which is used in the current work has 2688 cores and the price is only 1

  8. Synthetic Method for Oligonucleotide Block by Using Alkyl-Chain-Soluble Support.

    Science.gov (United States)

    Matsuno, Yuki; Shoji, Takao; Kim, Shokaku; Chiba, Kazuhiro

    2016-02-19

    A straightforward method for the synthesis of oligonucleotide blocks using a Cbz-type alkyl-chain-soluble support (Z-ACSS) attached to the 3'-OH group of 3'-terminal nucleosides was developed. The Z-ACSS allowed for the preparation of fully protected deoxyribo- and ribo-oligonucleotides without chromatographic purification and released dimer- to tetramer-size oligonucleotide blocks via hydrogenation using a Pd/C catalyst without significant loss or migration of protective groups such as 5'-end 4,4'-dimethoxtrityl, 2-cyanoethyl on internucleotide bonds, or 2'-TBS.

  9. Modifying nanoparticle shape by choice of synthetic method: Nanorods, spheres, mutipods, and gels

    Science.gov (United States)

    Shrestha, Khadga M.

    A series of nanoparticle synthesis methods were devised with the aim of controlling shape. CuO nanorods were synthesized by a hydrothermal treatment with different chemical combinations. Physical parameters: concentration, temperature, and aging time greatly affected the size, morphology and the composition of nanorods. These CuO nanomaterials were reduced to metallic copper at elevated temperature by 4% H2 diluted in helium while preserving the morphology. The CuO and Cu nanomaterials were employed for near infra-red (NIR) diffuse reflectance. Among them, CuO nanorods were found to be the best NIR diffuse reflectors, indicating potential application as NIR obscurants. Cu2O and its comoposite samples with different morphologies, some with unique morphologies, were synthesized by reducing Cu2+ precursors without using any surfactant. The effects of change of Cu-precursors, reducing agents, and other physical conditions such as temperature and pressure were investigated. Since Cu2O is a semiconductor (Eg ˜ 2.1 eV), these samples were used as photocatalyst for the degradation of methyl violet B solution under UV-vis light and as dark catalysts for decomposition of H2O2 to investigate the effect of morphology. The photocatalytic activity was found to be morphology dependent and the dark catalytic activity was found to be dependent on both surface area and morphology. Mixed oxides of MgO and TiO2 with different ratios, and pure TiO2 were synthesized by two methods---flame synthesis and aerogel. These mixed oxides were employed as photo-catalysts under UV-vis light to oxidize acetaldehyde. The mixed oxides with low content of MgO (˜ 2 mole %) were found to be more UV active photo-catalysts for the degradation of acetaldehyde than the degradation by TiO2. The mixed oxides prepared by the aerogel method were found to be superior photo-catalysts than the mixed oxides of equal ratio prepared by flame synthesis. Silica aerosol gels were prepared by two methods: detonation

  10. Recent progress in the direct synthesis of hierarchical zeolites: synthetic strategies and characterization methods

    KAUST Repository

    Liu, Zhaohui

    2017-06-16

    Hierarchically structured zeolites combine the merits of microporous zeolites and mesoporous materials to offer enhanced molecular diffusion and mass transfer without compromising the inherent catalytic activities and selectivity of zeolites. This short review gives an introduction to the synthesis strategies for hierarchically structured zeolites with emphasis on the latest progress in the route of ‘direct synthesis’ using various templates. Several characterization methods that allow us to evaluate the ‘quality’ of complex porous structures are also introduced. At the end of this review, an outlook is given to discuss some critical issues and challenges regarding the development of novel hierarchically structured zeolites as well as their applications.

  11. Effect of synthetic methods on the thermoelectrical properties of textured Bi2Ca2Co1.7Ox ceramics

    Directory of Open Access Journals (Sweden)

    Diez, J. C.

    2010-02-01

    Full Text Available Thermoelectric performances on cobaltite ceramics can be changed by grain orientation. This can be performed by directional solidification on samples prepared from different synthetic methods. Three synthetic methods, conventional solid state reaction, sol-gel and polymer solution were used for preparation of Bi2Ca2Co1.7Ox powders. The powders have been directionally grown, at a rate of 30 mm/h, by the laser floating zone method. In all the cases, the microstructure shows alternated layers, of Bi2Ca2Co2Ox and a Bi-Ca-O solid solution, with small CoO inclusions. It has been found an improvement on the power factor at 50 ºC for the solution methods with respect to the conventional solid sate sintered samples.Las prestaciones de las cerámicas basadas en óxidos de cobalto pueden modificarse por medio de la orientación de los granos. Este proceso puede llevarse a cabo mediante solidificación direccional de las muestras, que previamente han podido ser preparadas por diferentes rutas. En este trabajo se han utilizado tres métodos de síntesis, estado sólido, sol-gel y por vía polimérica, para preparar cerámicas con composición Bi2Ca2Co1.7Ox. Estos polvos se han crecido direccionalmente a 30 mm/h, por el método de zona flotante inducida por láser. En todos los casos la microestructura consiste en capas alternas, de Bi2Ca2Co2Ox y una solución sólida Bi-Ca-O, con pequeñas inclusiones de CoO. Se ha encontrado que los métodos de disolución mejoran el factor de potencia a 50 ºC, con respecto a los valores que se obtienen a través de los métodos de sinterizado en estado sólido.

  12. Evaluation of bio-conjugation methods for obtaining of synthetic positive control for IgM-capture ELISA

    Directory of Open Access Journals (Sweden)

    O. Y. Galkin

    2014-10-01

    Full Text Available The enzyme-linked immunosorbent assay (ELISA is the most informative and versatile method of serological diagnostics. The possibility of detecting by ELISA specific antibodies of different classes allow to differentiate primary infectious process and its remission, exacerbation and chronic disease (differential diagnosis. This approach is implemented in the methodology for evaluation of patients for the presence of humoral immune response to TORCH-infections pathogens (toxoplasmosis, rubella, cytomegalovirus, herpes simplex viruses’ infections, and some others. Therefore, testing for presence of specific IgG and IgM antibodies against TORCH-infections pathogens in blood serum is an important element of motherhood and childhood protection. The essential problem in the production of IgM-capture ELISA diagnostic kits is obtaining of positive control. The classic version of positive control is human blood serum (plasma containing specific antibodies. But specific IgM-positive sera are insignificant raw materials. This fact can seriously restrict the production of diagnostic kits, especially in the event of large-scale production. We have suggested the methodological approach to using of synthetic positive controls in IgM-capture ELISA kits based on conjugate of normal human IgM and monoclonal antibodies against horseradish peroxidase. It is found that this task can be fulfilled by means of NHS ester-maleimide-mediated conjugation (by sulfosuccinimidyl-4-(N-maleimidomethylcyclohexane-1-carboxylate, reductive amination-mediated conjugation (by sodium periodate and glutaraldehyde-mediated conjugation. It was found that conjugates of normal human IgM and monoclonal antibodies against horseradish peroxidase obtained using NHS ester-mediated maleimide conjugation and periodate method were similar by molecular weight, whereas conjugate synthesized by glutaraldehyde method comprised at least three types of biopolymers with close molecular weight. It was

  13. Method validation and measurement uncertainty for the simultaneous determination of synthetic phenolic antioxidants in edible oils commonly consumed in Korea.

    Science.gov (United States)

    Kim, Jae-Min; Choi, Seung-Hyun; Shin, Gi-Hae; Lee, Jin-Ha; Kang, Seong-Ran; Lee, Kyun-Young; Lim, Ho-Soo; Kang, Tae Seok; Lee, Ok-Hwan

    2016-12-15

    This study investigated a method for the validation and determination of measurement uncertainty for the simultaneous determination of synthetic phenolic antioxidants (SPAs) such as propyl gallate (PG), octyl gallate (OG), dodecyl gallate (DG), 2,4,5-trihydroxy butyrophenone (THBP), tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) in edible oils commonly consumed in Korea. The validated method was able to extract SPA residues under the optimized HPLC-UV and LC-MS/MS conditions. Furthermore, the measurement of uncertainty was evaluated based on the precision study. For HPLC-UV analysis, the recoveries of SPAs ranged from 91.4% to 115.9% with relative standard deviations between 0.3% and 11.4%. In addition, the expanded uncertainties of the SPAs ranged from 0.15 to 5.91. These results indicate that the validated method is appropriate for the extraction and determination of SPAs and can be used to verify the safety of edible oil products containing SPAs residues. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Improvements in or relating to method of preparing porous material/synthetic polymer composites

    International Nuclear Information System (INIS)

    Hills, P.R.; McGahan, D.J.

    1976-01-01

    A method for preparing a composite material is described comprising polymerising a monoethylenically unsaturated monomer of a mixture of copolymerisable monoethylenically unsaturated monomers in a porous material, excluding a porous natural cellulosic fibre material, the polymerisable liquid being admixed in the porous material with a saturated aliphatic hydrocarbon or a halogen derivative thereof. It is preferable that the polymerisable liquid and the hydrocarbon or halogen derivative are present in the porous material. Impregnation may be carried out by a vacuum technique or by simple immersion. The monomers that may be used are listed, but a mixture of styrene and acrylonitrile is preferred in the proportions 60 : 40 by volume. Polymerisation may be effected by irradiation, preferably with 60 Co γ-radiation. Suitable porous materials include concrete, stone, and fibreboard. If concrete is used the composite material may be used for pressure pipes and other articles normally made of steel. Examples of the application of the process are given. (U.K.)

  15. Measurement of acceleration while walking as an automated method for gait assessment in dairy cattle

    DEFF Research Database (Denmark)

    Chapinal, N.; de Passillé, A.M.; Pastell, M.

    2011-01-01

    The aims were to determine whether measures of acceleration of the legs and back of dairy cows while they walk could help detect changes in gait or locomotion associated with lameness and differences in the walking surface. In 2 experiments, 12 or 24 multiparous dairy cows were fitted with five 3......-dimensional accelerometers, 1 attached to each leg and 1 to the back, and acceleration data were collected while cows walked in a straight line on concrete (experiment 1) or on both concrete and rubber (experiment 2). Cows were video-recorded while walking to assess overall gait, asymmetry of the steps......, and walking speed. In experiment 1, cows were selected to maximize the range of gait scores, whereas no clinically lame cows were enrolled in experiment 2. For each accelerometer location, overall acceleration was calculated as the magnitude of the 3-dimensional acceleration vector and the variance of overall...

  16. Radiation safety assessment of treatment teletherapy linear accelerators using the method of the risk matrix

    International Nuclear Information System (INIS)

    Dumenigo Gonzalez, Cruz; Vilaragut Llanes, Juan J.; Morales Lopez, Jorge L.

    2009-01-01

    Accidents in the world of radiation, demonstrating the need for deepen security assessments. This study evaluates the safety of the treatment of teletherapy linear accelerator (LINAC) at a hospital in Cuba, based on applying the method Risk Matrix. This method has been used for many years in conventional industry, is simple, easy to apply and is based on the equation General risk R = f * P * C (where: f frequency of occurrence of the initiating event, P probability of failure of all barriers and magnitude of the consequences C expected). We have evaluated 140 accident sequences that were identified during the analysis of the treatment process. It was identified that 5 sequences are associated with the level of risk is very low, 96 low-risk, high risk and 39 with no very high risk. All accident sequences associated with high risk (considered unacceptable), have an impact on patients, and no concerns workers and public, which reaffirms that major security problems are related to radiation protection of patients. 34 sequences accidental high risk are associated with human errors and failures only 5 to equipment (LINAC, TPS, TAC, etc.). demonstrating the importance of human error. It shows that 35 of the 39 high-risk accident sequences leading to serious or very serious consequences for patients, which would mean the death of one or more patients, making specific recommendations to reduce risk in these cases. The findings of this work and regulators allow users to refine their programs quality assurance and inspection and suggest the hospital management, prioritize material resources according to criteria of irrigation management. (author)

  17. Use of accelerated radioimmunoassay methods for LH, HCG, HPL and α-FP determination in gynecology and obstetrics

    International Nuclear Information System (INIS)

    Grzes, A.

    1976-01-01

    Accelerated methods of determining LH, HCG, HPL and α-FP in clinical practice are discussed. The kinetic determination of LH permits defining ovulation time, the determination of HCG permits early pregnancy ascertainment. The determination of HPL serves the diagnosis of placental functions while α-FP determination in the amniotic fluid may show disorders in the fetal development. (L.O.)

  18. Method for controlling an accelerator-type neutron source, and a pulsed neutron source

    International Nuclear Information System (INIS)

    Givens, W.W.

    1991-01-01

    The patent deals with an accelerator-type neutron source which employs a target, an ionization section and a replenisher for supplying accelerator gas. A positive voltage pulse is applied to the ionization section to produce a burst of neutrons. A negative voltage pulse is applied to the ionization section upon the termination of the positive voltage pulse to effect a sharp cut-off to the burst of neutrons. 4 figs

  19. Cavity pressure acceleration: An efficient laser-based method of production of high-velocity macroparticles

    Czech Academy of Sciences Publication Activity Database

    Borodziuk, S.; Kasperczuk, A.; Pisarczyk, T.; Badziak, J.; Chodukowski, T.; Ullschmied, Jiří; Krouský, Eduard; Mašek, Karel; Pfeifer, Miroslav; Rohlena, Karel; Skála, Jiří; Pisarczyk, P.

    2009-01-01

    Roč. 95, č. 23 (2009), s. 231501-231501 ISSN 0003-6951 R&D Projects: GA MŠk(CZ) LC528; GA MŠk(CZ) 7E09092 Institutional research plan: CEZ:AV0Z20430508; CEZ:AV0Z10100523 Keywords : Laser -plasma interaction * PALS laser * cavity pressure acceleration * acceleration of macroparticles Subject RIV: BH - Optics, Masers, Laser s Impact factor: 3.554, year: 2009

  20. Ion acceleration from intense laser-generated plasma: methods, diagnostics and possible applications

    Directory of Open Access Journals (Sweden)

    Torrisi Lorenzo

    2015-06-01

    Full Text Available Many parameters of non-equilibrium plasma generated by high intensity and fast lasers depend on the pulse intensity and the laser wavelength. In conditions favourable for the target normal sheath acceleration (TNSA regime the ion acceleration from the rear side of the target can be enhanced by increasing the thin foil absorbance through the use of nanoparticles and nanostructures promoting the surface plasmon resonance effect. In conditions favourable for the backward plasma acceleration (BPA regime, when thick targets are used, a special role is played by the laser focal position with respect to the target surface, a proper choice of which may result in induced self-focusing effects and non-linear acceleration enhancement. SiC detectors employed in the time-of-flight (TOF configuration and a Thomson parabola spectrometer permit on-line diagnostics of the ion streams emitted at high kinetic energies. The target composition and geometry, apart from the laser parameters and to the irradiation conditions, allow further control of the plasma characteristics and can be varied by using advanced targets to reach the maximum ion acceleration. Measurements using advanced targets with enhanced the laser absorption effect in thin films are presented. Applications of accelerated ions in the field of ion source, hadrontherapy and nuclear physics are discussed.

  1. A Vector Flow Imaging Method for Portable Ultrasound Using Synthetic Aperture Sequential Beamforming

    DEFF Research Database (Denmark)

    di Ianni, Tommaso; Villagómez Hoyos, Carlos Armando; Ewertsen, Caroline

    2017-01-01

    imaging region. Six focused emissions are used to create a high-resolution image (HRI), and a dual-stage beamforming approach is used to lower the data throughput between the probe and the processing unit. The transmit/receive focal points are laterally separated to obtain a TO in the HRI that allows...... for the velocity estimation along the lateral and axial directions using a phase-shift estimator. The performance of the method was investigated with constant flow measurements in a flow rig system using the SARUS scanner and a 4.1-MHz linear array. A sequence was designed with interleaved B-mode and flow......, and the standard deviation (SD) was between 6% and 9.6%. The axial bias was lower than 1% with an SD around 2%. The mean estimated angles were 66.70° ± 2.86°, 72.65° ± 2.48°, and 89.13° ± 0.79° for the three cases. A proof-of-concept demonstration of the real-time processing and wireless transmission was tested...

  2. Fungal synthesis of chiral phosphonic synthetic platform - Scope and limitations of the method.

    Science.gov (United States)

    Serafin-Lewańczuk, Monika; Klimek-Ochab, Magdalena; Brzezińska-Rodak, Małgorzata; Żymańczyk-Duda, Ewa

    2018-04-01

    Chiral hydroxyphosphonates due to their wide range of biological properties are industrially important chemicals. Chemical synthesis of their optical isomers is expensive, time consuming and not friendly to the environment, so biotransformations are under consideration. Among others, these compounds act as enzymes inhibitors. This makes the bioconversions of phosphonates, especially scaling experiments, hard to perform. Biocatalysis is one of the methods that can be applied in synthesis of optically pure compounds. To increase the efficiency of the process with whole cell biocatalysts, it is essential to ensure optimal reaction conditions that minimize cellular stress and can enhance the metabolic activity of cells. The present investigation focuses on the scaling up of the kinetic resolution of racemic mixture of 2-butyryloxy-2-(ethoxy-P-phenylphosphinyl)acetic acid, applying free and immobilized form of the fungal biocatalysts and two operation systems: shake flask and recirculated fixed-bed batch reactor. Protocols of effective mycelium immobilization on polyurethane foams were set for T. purpurogenus IAFB 2512, F. oxysporum, P. commune. The best results of biotransformation were obtained with the immobilized P. commune in the column recirculated fixed-bed batch reactor. The conversion reaches 56% (maximal for the kinetic process) and the enantiomeric enrichment of the isomers mixture ranges between 82 and 93% (93% for ester of R P ,R conformation). All biocatalysts exhibit S P -preference toward tested compound, what is essential because of importance of the phosphorus atom chirality for its biological activity. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Optimization of accelerator parameters using normal form methods on high-order transfer maps

    Energy Technology Data Exchange (ETDEWEB)

    Snopok, Pavel [Michigan State Univ., East Lansing, MI (United States)

    2007-05-01

    Methods of analysis of the dynamics of ensembles of charged particles in collider rings are developed. The following problems are posed and solved using normal form transformations and other methods of perturbative nonlinear dynamics: (1) Optimization of the Tevatron dynamics: (a) Skew quadrupole correction of the dynamics of particles in the Tevatron in the presence of the systematic skew quadrupole errors in dipoles; (b) Calculation of the nonlinear tune shift with amplitude based on the results of measurements and the linear lattice information; (2) Optimization of the Muon Collider storage ring: (a) Computation and optimization of the dynamic aperture of the Muon Collider 50 x 50 GeV storage ring using higher order correctors; (b) 750 x 750 GeV Muon Collider storage ring lattice design matching the Tevatron footprint. The normal form coordinates have a very important advantage over the particle optical coordinates: if the transformation can be carried out successfully (general restrictions for that are not much stronger than the typical restrictions imposed on the behavior of the particles in the accelerator) then the motion in the new coordinates has a very clean representation allowing to extract more information about the dynamics of particles, and they are very convenient for the purposes of visualization. All the problem formulations include the derivation of the objective functions, which are later used in the optimization process using various optimization algorithms. Algorithms used to solve the problems are specific to collider rings, and applicable to similar problems arising on other machines of the same type. The details of the long-term behavior of the systems are studied to ensure the their stability for the desired number of turns. The algorithm of the normal form transformation is of great value for such problems as it gives much extra information about the disturbing factors. In addition to the fact that the dynamics of particles is represented

  4. Predictors of stress and coping strategies of US accelerated vs. generic Baccalaureate Nursing students: an embedded mixed methods study.

    Science.gov (United States)

    Wolf, Linda; Stidham, Andrea Warner; Ross, Ratchneewan

    2015-01-01

    Stress is an inevitable part of life and is especially pervasive in the lives of nursing students. Identifying the predictors of stress as well as coping strategies used can allow for the implementation of appropriate coping interventions to assist in the management of stress in nursing students. Mixed methods research that has been undertaken to gain an understanding about student stress, especially juxtaposing generic versus accelerated nursing students could not be identified. (1) Identify predictors of stress between accelerated and generic Baccalaureate Nursing (BSN) students; and (2) Describe stressors and coping strategies used by accelerated students in comparison with generic students. Embedded mixed methods study. Accelerated and generic BSN third- and fourth-year nursing students at two Midwestern universities. 210 participants: accelerated (n=75) and generic (n=135). A questionnaire packet, including demographics, history of depression, the Perceived Stress Questionnaire, Rosenberg Self-Esteem Scale, Multidimensional Scale of Perceived Social Support, and open-ended questions were administered to students at the end of a class. Simultaneous multiple regression was used to examine predictors of stress. Content analysis was used to analyze qualitative data. Predictors of stress for both the accelerated and generic groups included history of depression, year in the program, emotional support, and self-esteem. Fear of failure and clinical incompetence, problematic relationships, and time management issues were identified as major stressors. Coping strategies used by both groups included positive thinking and social support. Senior students with a history of depression, low self-esteem, and little social support were more likely to experience high levels of stress. This gives educators the potential to identify at risk students and establish stress reduction programs. Encouraging students to use individualized coping strategies will be beneficial. Copyright

  5. Unconditionally stable diffusion-acceleration of the transport equation

    International Nuclear Information System (INIS)

    Larson, E.W.

    1982-01-01

    The standard iterative procedure for solving fixed-source discrete-ordinates problems converges very slowly for problems in optically thick regions with scattering ratios c near unity. The diffusion-synthetic acceleration method has been proposed to make use of the fact that for this class of problems, the diffusion equation is often an accurate approximation to the transport equation. However, stability difficulties have historically hampered the implementation of this method for general transport differencing schemes. In this article we discuss a recently developed procedure for obtaining unconditionally stable diffusion-synthetic acceleration methods for various transport differencing schemes. We motivate the analysis by first discussing the exact transport equation; then we illustrate the procedure by deriving a new stable acceleration method for the linear discontinuous transport differencing scheme. We also provide some numerical results

  6. Synthetic Cannabinoids

    Directory of Open Access Journals (Sweden)

    Aslihan Okan Ibiloglu

    2017-09-01

    Full Text Available Synthetic cannabinoids which is a subgroup of cannabinoids are commonly used for recreational drug use throughout the whole world. Although both marijuana and synthetic cannabinoids stimulate the same receptors, cannabinoid receptor 1 (CB1 and cannabinoid receptor 2 (CB2, studies have shown that synthetic cannabinoids are much more potent than marijuana. The longer use of synthetic cannabinoids can cause severe physical and psychological symptoms that might even result in death, similar to many known illicit drugs. Main treatment options mostly involve symptom management and supportive care. The aim of this article is to discuss clinical and pharmacological properties of the increasingly used synthetic cannabinoids. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2017; 9(3.000: 317-328

  7. Chemical Synthesis Accelerated by Paper Spray: The Haloform Reaction

    Science.gov (United States)

    Bain, Ryan M.; Pulliam, Christopher J.; Raab, Shannon A.; Cooks, R. Graham

    2016-01-01

    In this laboratory, students perform a synthetic reaction in two ways: (i) by traditional bulk-phase reaction and (ii) in the course of reactive paper spray ionization. Mass spectrometry (MS) is used both as an analytical method and a means of accelerating organic syntheses. The main focus of this laboratory exercise is that the same ionization…

  8. Synthetic efforts toward the Lycopodium alkaloids inspires a hydrogen iodide mediated method for the hydroamination and hydroetherification of olefins.

    Science.gov (United States)

    Leger, Paul R; Murphy, Rebecca A; Pushkarskaya, Eugenia; Sarpong, Richmond

    2015-03-09

    Progress toward the total syntheses of a diverse set of fawcettimine-type Lycopodium alkaloids via a "Heathcock-type" 6-5-9 tricycle is disclosed. This route features an intermolecular Diels-Alder cycloaddition to rapidly furnish the 6-5-fused bicycle and a highly chemoselective directed hydrogenation to build the azonane fragment. While conducting these synthetic studies, trimethylsilyl iodide was found to effect a hydroamination reaction to furnish the tetracyclic core of serratine and related natural products. This observation has been expanded into a general method for the room temperature hydroamination of unactivated olefins with tosylamides utilizing catalytic "anhydrous" HI (generated in situ from trimethylsilyl iodide and water). The presence of the iodide anion is critical to the success of this Brønsted acid catalyzed protocol, possibly due to its function as a weakly coordinating anion. These conditions also effect the analogous hydroetherification reaction of alcohols with unactivated olefins. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Effects of solution pH and synthetic method on destabilization process of polytitanium-silicate-chloride.

    Science.gov (United States)

    Huang, Xin; Gao, Baoyu; Sun, Yangyang; Yue, Qinyan; Wang, Yan; Li, Qian

    2016-07-05

    Effect of solution pH on coagulation performance and flock properties of a novel inorganic polymer coagulant-polytitanium-silicate-chloride (PTSC) in humic acid-kaolin water treatment was investigated in this work. PTSC was synthesized by two approaches: composite and co-complexion, denoted as PTSCm and PTSCc respectively. The effect of the synthetic method was also considered. Results indicated that turbidity and DOM removal were improved by addition of polysilicic acid, especially under acidic condition. PTSCc achieved slightly better DOM removal than that of PTSCm. Flocks formed under acidic condition was smaller than those form under alkaline condition. In addition, flocks formed by PTSCc were larger than PTSCm flocks. Results also indicated that flock strength and recovery ability was slightly improved by the addition of PSiA. Moreover, under acidic condition, PTSC flocks had larger fractal dimension with more compact structure, especially for PTSCm flocks. In contrast, they were looser compared with PTC flock, especially for PTSCm flocks under neutral and alkaline conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Electron Acceleration in a Turbulent Current Sheet - Comparison of GCA and HARHA Methods

    Czech Academy of Sciences Publication Activity Database

    Kramoliš, D.; Varady, Michal; Bárta, Miroslav

    2016-01-01

    Roč. 40, č. 1 (2016), s. 69-77 ISSN 1845-8319. [Hvar Astrophysical Colloquium /14./. Hvar, 26.09.2016-30.09.2016] R&D Projects: GA ČR(CZ) GA16-18495S Institutional support: RVO:67985815 Keywords : magnetic reconnection * current sheet * electron acceleration Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  11. Accelerated Vocational Training for Adults, a Comparative Study: Objectives, Organization, Syllabuses and Methods, Future Prospects.

    Science.gov (United States)

    Martin, Victor

    The program of Accelerated Vocational Training (AVT) for adults in France, Great Britain, The Netherlands, and Belgium, originally developed mainly in the basic manual crafts of building and metalwork, is now covering more occupations and is intended to develop trade skills to a level of qualification comparable, if not equivalent, to that which…

  12. Multiclass analytical method for the determination of natural/synthetic steroid hormones, phytoestrogens, and mycoestrogens in milk and yogurt.

    Science.gov (United States)

    Socas-Rodríguez, Bárbara; Lanková, Darina; Urbancová, Kateřina; Krtková, Veronika; Hernández-Borges, Javier; Rodríguez-Delgado, Miguel Ángel; Pulkrabová, Jana; Hajšlová, Jana

    2017-07-01

    Within this study, a new method enabling monitoring of various estrogenic substances potentially occurring in milk and dairy products was proposed. Groups of compounds fairly differing in physico-chemical properties and biological activity were analyzed: four natural estrogens, four synthetic estrogens, five mycoestrogens, and nine phytoestrogens. Since they may pass into milk mainly in glucuronated and sulfated forms, an enzymatic hydrolysis was involved prior to the extraction based on the QuEChERS methodology. For the purification of the organic extract, a dispersive solid-phase extraction (d-SPE) with sorbent C18 was applied. The final analysis was performed by ultra-high-performance liquid chromatography (UHPLC) coupled with triple quadrupole tandem mass spectrometry (MS/MS). Method recovery ranged from 70 to 120% with a relative standard deviation (RSD) value lower than 20% and limits of quantification (LOQs) in the range of 0.02-0.60 μg/L (0.2-6.0 μg/kg dry weight) and 0.02-0.90 μg/kg (0.2-6.0 μg/kg dry weight) for milk and yogurt, respectively. The new procedure was applied for the investigation of estrogenic compounds in 11 milk samples and 13 yogurt samples from a Czech retail market. Mainly phytoestrogens were found in the studied samples. The most abundant compounds were equol and enterolactone representing 40-90% of all estrogens. The total content of phytoestrogens (free and bound) was in the range of 149-3870 μg/kg dry weight. This amount is approximately 20 times higher compared to non-bound estrogens.

  13. Efficient Homodifunctional Bimolecular Ring-Closure Method for Cyclic Polymers by Combining RAFT and Self-Accelerating Click Reaction.

    Science.gov (United States)

    Qu, Lin; Sun, Peng; Wu, Ying; Zhang, Ke; Liu, Zhengping

    2017-08-01

    An efficient metal-free homodifunctional bimolecular ring-closure method is developed for the formation of cyclic polymers by combining reversible addition-fragmentation chain transfer (RAFT) polymerization and self-accelerating click reaction. In this approach, α,ω-homodifunctional linear polymers with azide terminals are prepared by RAFT polymerization and postmodification of polymer chain end groups. By virtue of sym-dibenzo-1,5-cyclooctadiene-3,7-diyne (DBA) as small linkers, well-defined cyclic polymers are then prepared using the self-accelerating double strain-promoted azide-alkyne click (DSPAAC) reaction to ring-close the azide end-functionalized homodifunctional linear polymer precursors. Due to the self-accelerating property of DSPAAC ring-closing reaction, this novel method eliminates the requirement of equimolar amounts of telechelic polymers and small linkers in traditional bimolecular ring-closure methods. It facilitates this method to efficiently and conveniently produce varied pure cyclic polymers by employing an excess molar amount of DBA small linkers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Simultaneous Determination of 6-Mercaptopurine and its Oxidative Metabolites in Synthetic Solutions and Human Plasma using Spectrophotometric Multivariate Calibration Methods

    Directory of Open Access Journals (Sweden)

    Mohammad-Reza Rashidi

    2011-06-01

    Full Text Available Introduction: 6-Mercaptopurine (6MP is an important chemotherapeutic drug in the conventional treatment of childhood acute lymphoblastic leukemia (ALL. It is catabolized to 6-thiouric acid (6TUA through 8-hydroxo-6-mercaptopurine (8OH6MP or 6-thioxanthine (6TX intermediates. Methods: High-performance liquid chromatography (HPLC is usually used to determine the contents of therapeutic drugs, metabolites and other important biomedical analytes in biological samples. In the present study, the multivariate calibration methods, partial least squares (PLS-1 and principle component regression (PCR have been developed and validated for the simultaneous determination of 6MP and its oxidative metabolites (6TUA, 8OH6MP and 6TX without analyte separation in spiked human plasma. Mixtures of 6MP, 8-8OH6MP, 6TX and 6TUA have been resolved by PLS-1 and PCR to their UV spectra. Results: Recoveries (% obtained for 6MP, 8-8OH6MP, 6TX and 6TUA were 94.5-97.5, 96.6-103.3, 95.1-96.9 and 93.4-95.8, respectively, using PLS-1 and 96.7-101.3, 96.2-98.8, 95.8-103.3 and 94.3-106.1, respectively, using PCR. The NAS (Net analyte signal concept was used to calculate multivariate analytical figures of merit such as limit of detection (LOD, selectivity and sensitivity. The limit of detections for 6MP, 8-8OH6MP, 6TX and 6TUA were calculated to be 0.734, 0.439, 0.797 and 0.482 µmol L-1, respectively, using PLS and 0.724, 0.418, 0783 and 0.535 µmol L-1, respectively, using PCR. HPLC was also applied as a validation method for simultaneous determination of these thiopurines in the synthetic solutions and human plasma. Conclusion: Combination of spectroscopic techniques and chemometric methods (PLS and PCR has provided a simple but powerful method for simultaneous analysis of multicomponent mixtures.

  15. Improvement of thermoelectric properties of Bi2Sr2Co1.8Ox through solution synthetic methods

    Directory of Open Access Journals (Sweden)

    Diez, J. C.

    2012-02-01

    Full Text Available Several solution synthetic methods, sol-gel and a polymeric route, have been studied in order to obtain Bi2Sr2Co1.8Ox ceramics with improved thermoelectric properties, compared to the classical solid state reaction. The products obtained by these different methods have been compared using DTA-TGA, powder X-ray diffraction, scanning electron microscopy, and thermoelectric characterizations. All the samples obtained by solution synthesis show higher homogeneity and lower content of secondary phases. The main differences in thermoelectrical properties are due to the decrease of electrical resistivity in samples obtained by solution methods, compared with the solid state obtained samples. Between them, the decrease is especially high for those samples prepared by the polymer solution method. Therefore, the polymeric solution synthesis route is shown to yield a power factor four times higher than the obtained for the solid state and sol-gel methods at room temperature.Se han obtenido cerámicas termoeléctricas Bi2Sr2Co1.8Ox utilizando varios métodos de síntesis, el clásico por estado sólido, sol-gel y de matriz polimérica. Se han comparado los productos obtenidos por las diferentes vías a través de técnicas de DTA-TGA, difracción de rayos X en polvo, microscopía electrónica de barrido y de caracterización termoeléctrica. Todas las muestras obtenidas por los métodos en disolución poseen una mayor homogeneidad y menor contenido de fases secundarias. La principal diferencia en las propiedades termoeléctricas es debida a la disminución de la resistividad eléctrica en las muestras obtenidas por medio de métodos en disolución, comparado con las que se obtienen por estado sólido. Entre ellas, la reducción de la resistividad es mucho mayor para las que se obtienen por el método de matriz polimérica. Además, los materiales obtenidos por este último método poseen un factor de potencia, a temperatura ambiente, cuatro veces mayor que

  16. Multi-frequency accelerating strategy for the contrast source inversion method of ultrasound waveform tomography using pulse data

    Science.gov (United States)

    Lin, Hongxiang; Azuma, Takashi; Qu, Xiaolei; Takagi, Shu

    2017-03-01

    In this work, we construct a multi-frequency accelerating strategy for the contrast source inversion (CSI) method using pulse data in the time domain. CSI is a frequency-domain inversion method for ultrasound waveform tomography that does not require the forward solver through the process of reconstruction. Several prior researches show that the CSI method has a good performance of convergence and accuracy in the low-center-frequency situation. In contrast, utilizing the high-center-frequency data leads to a high-resolution reconstruction but slow convergence on large numbers of grid. Our objective is to take full advantage of all low frequency components from pulse data with the high-center-frequency data measured by the diagnostic device. First we process the raw data in the frequency domain. Then multi-frequency accelerating strategy helps restart CSI in the current frequency using the last iteration result obtained from the lower frequency component. The merit of multi- frequency accelerating strategy is that computational burden decreases at the first few iterations. Because the low frequency component of dataset computes on the coarse grid with assuming a fixed number of points per wavelength. In the numerical test, the pulse data were generated by the K-wave simulator and have been processed to meet the computation of the CSI method. We investigate the performance of the multi-frequency and single-frequency reconstructions and conclude that the multi-frequency accelerating strategy significantly enhances the quality of the reconstructed image and simultaneously reduces the average computational time for any iteration step.

  17. Synthetic oils

    Science.gov (United States)

    Hatton, R. E.

    1973-01-01

    Synthetic lubricants are discussed by chemical class and their general strengths and weaknesses in terms of lubrication properties are analyzed. Comparative ratings are given for 14 chemical classes and are used as a guide for lubricant selection. The effects of chemical structure on the properties of the lubricant are described with special emphasis on thermal stability. The diversity of synthetic lubricants which is provided by the wide range of properties permits many applications, some of which are reported.

  18. Ergonomic assessment of brake and accelerator mechanisms of MF285 and MF399 tractors using electromyography method

    Directory of Open Access Journals (Sweden)

    A Nikkhah

    2016-04-01

    Full Text Available Introduction: Too many people are working in the agricultural sector and therefore, pay more attention to the safety and health at work in the agricultural sector is important. This issue is more important in developing industrial countries where the level of the ergonomic working condition is less than that of developed countries. Attention to ergonomic condition of agricultural machinery drivers is one of the goals of agricultural mechanization. Therefore, in this study the ergonomic conditions of brake and accelerator mechanisms for MF285 and MF399 tractor's drivers were investigated using a new method. Materials and Methods: 25 people were selected for experiment. The electrical activity of Medialis gastrocnemius, Lateralis gastrocnemius, Vastus medialis, Vastus lateralis, Quadratus Lumborum and Trapezius muscles of drivers before and during pressing the pedal and after rest time were recorded using Biovision device. Measurements were performed for each person on each muscle 30 seconds before pressing the pedal, 60 seconds after pressing the pedal and after 60 seconds of rest. For all drivers, the muscles on the right side (brake and accelerator side have been selected and tested. The measurements were performed in compliance with appropriate time intervals between the measurements. Results and Discussion: Ergonomic assessment of brake pedal: The results showed that the RMS electrical activity of muscles of Vastus medialis and Medial gastrocnemius, during 60 seconds braking were 2.47 and 1.97. So, Vastus medialis and Medial gastrocnemius had the highest stress during pressing the MF399 tractor's brake pedal. Moreover, the Medial gastrocnemius and Lateral gastrocnemius with RMS electrical activity ratio of 2.47 and 1.74 had the highest RMS electrical activity ratio respectively, during 60 seconds braking compared to before braking of MF285 tractor. The comparison of results showed that the Vastus medialis and Trapezius had the higher stress

  19. Method and Apparatus for measuring Gravitational Acceleration Utilizing a high Temperature Superconducting Bearing

    Energy Technology Data Exchange (ETDEWEB)

    Hull, John R.

    1998-11-06

    Gravitational acceleration is measured in all spatial dimensions with improved sensitivity by utilizing a high temperature superconducting (HTS) gravimeter. The HTS gravimeter is comprised of a permanent magnet suspended in a spaced relationship from a high temperature superconductor, and a cantilever having a mass at its free end is connected to the permanent magnet at its fixed end. The permanent magnet and superconductor combine to form a bearing platform with extremely low frictional losses, and the rotational displacement of the mass is measured to determine gravitational acceleration. Employing a high temperature superconductor component has the significant advantage of having an operative temperature at or below 77K, whereby cooling maybe accomplished with liquid nitrogen.

  20. Method and apparatus for measuring gravitational acceleration utilizing a high temperature superconducting bearing

    Science.gov (United States)

    Hull, John R.

    2000-01-01

    Gravitational acceleration is measured in all spatial dimensions with improved sensitivity by utilizing a high temperature superconducting (HTS) gravimeter. The HTS gravimeter is comprised of a permanent magnet suspended in a spaced relationship from a high temperature superconductor, and a cantilever having a mass at its free end is connected to the permanent magnet at its fixed end. The permanent magnet and superconductor combine to form a bearing platform with extremely low frictional losses, and the rotational displacement of the mass is measured to determine gravitational acceleration. Employing a high temperature superconductor component has the significant advantage of having an operating temperature at or below 77K, whereby cooling may be accomplished with liquid nitrogen.

  1. Application of High-performance Visual Analysis Methods to Laser Wakefield Particle Acceleration Data

    International Nuclear Information System (INIS)

    Rubel, Oliver; Prabhat, Mr.; Wu, Kesheng; Childs, Hank; Meredith, Jeremy; Geddes, Cameron G.R.; Cormier-Michel, Estelle; Ahern, Sean; Weber, Gunther H.; Messmer, Peter; Hagen, Hans; Hamann, Bernd; Bethel, E. Wes

    2008-01-01

    Our work combines and extends techniques from high-performance scientific data management and visualization to enable scientific researchers to gain insight from extremely large, complex, time-varying laser wakefield particle accelerator simulation data. We extend histogram-based parallel coordinates for use in visual information display as well as an interface for guiding and performing data mining operations, which are based upon multi-dimensional and temporal thresholding and data subsetting operations. To achieve very high performance on parallel computing platforms, we leverage FastBit, a state-of-the-art index/query technology, to accelerate data mining and multi-dimensional histogram computation. We show how these techniques are used in practice by scientific researchers to identify, visualize and analyze a particle beam in a large, time-varying dataset

  2. Study on Calculation Methods for Sampling Frequency of Acceleration Signals in Gear System

    Directory of Open Access Journals (Sweden)

    Feibin Zhang

    2013-01-01

    Full Text Available The vibration acceleration signal mechanisms in normal and defect gears are studied. An improved bending-torsion vibration model is established, in which the effect of time-varying meshing stiffness and damping, torsional stiffness for transmission shaft, elastic bearing support, the driving motor, and external load are taken into consideration. Then, vibration signals are simulated based on the model under diverse sampling frequencies. The influences of input shaft's rotating frequency, the teeth number, and module of gears are investigated by the analysis of the simulation signals. Finally, formulas are proposed to calculate the acceleration signal bandwidth and the critical and recommended sampling frequencies of the gear system. The compatibility of the formulas is discussed when there is a crack in the tooth root. The calculation results agree well with the experiments.

  3. Development and testing of a superconducting acceleration resonator using new methods in design and fabrication

    International Nuclear Information System (INIS)

    Steck, M.

    1986-01-01

    A superconducting quarter-wave resonator at 325 MHz was studied for the implementation at the Heidelberg post-accelerator. Using the computer programs SUPERFISH and URMEL the first design derived from analytical approaches was optimized regarding the superconducting operation. The measurements on the model showed good agreement with the calculations. By modification of the standard techniques the fabrication of the resonator body and the preparation of the superconducting surface could be simplified. On the superconducting resonator 1 μm thick superconducting surfaces of pure lead as well as a lead/tin alloy were tested. Thereby with lead a quality of the resonator Q 0 =8.5.10 7 and a maximal electrical acceleration field in the continuous region of epsilonsub(acc)=2.16 MV/m at Q=1.10 7 were reached. The measurements with a surface of lead/tin yielded Q 0 =1.4.10 8 and as maximal acceleration field epsilonsub(acc)=1.93 MV/m at Q=1.10 7 . A further increasing of the maximal electric field by conditioning of the resonator can be expected because of the test results. The excellent mechanical stability not reachable with other resonator types which manifests by a static frequency shift of 4 Hz/(MV/m) 2 and rapid frequency oscillations [de

  4. A GPU-accelerated semi-implicit fractional-step method for numerical solutions of incompressible Navier-Stokes equations

    Science.gov (United States)

    Ha, Sanghyun; Park, Junshin; You, Donghyun

    2018-01-01

    Utility of the computational power of Graphics Processing Units (GPUs) is elaborated for solutions of incompressible Navier-Stokes equations which are integrated using a semi-implicit fractional-step method. The Alternating Direction Implicit (ADI) and the Fourier-transform-based direct solution methods used in the semi-implicit fractional-step method take advantage of multiple tridiagonal matrices whose inversion is known as the major bottleneck for acceleration on a typical multi-core machine. A novel implementation of the semi-implicit fractional-step method designed for GPU acceleration of the incompressible Navier-Stokes equations is presented. Aspects of the programing model of Compute Unified Device Architecture (CUDA), which are critical to the bandwidth-bound nature of the present method are discussed in detail. A data layout for efficient use of CUDA libraries is proposed for acceleration of tridiagonal matrix inversion and fast Fourier transform. OpenMP is employed for concurrent collection of turbulence statistics on a CPU while the Navier-Stokes equations are computed on a GPU. Performance of the present method using CUDA is assessed by comparing the speed of solving three tridiagonal matrices using ADI with the speed of solving one heptadiagonal matrix using a conjugate gradient method. An overall speedup of 20 times is achieved using a Tesla K40 GPU in comparison with a single-core Xeon E5-2660 v3 CPU in simulations of turbulent boundary-layer flow over a flat plate conducted on over 134 million grids. Enhanced performance of 48 times speedup is reached for the same problem using a Tesla P100 GPU.

  5. Synthetic biology for microbial heavy metal biosensors.

    Science.gov (United States)

    Kim, Hyun Ju; Jeong, Haeyoung; Lee, Sang Jun

    2018-02-01

    Using recombinant DNA technology, various whole-cell biosensors have been developed for detection of environmental pollutants, including heavy metal ions. Whole-cell biosensors have several advantages: easy and inexpensive cultivation, multiple assays, and no requirement of any special techniques for analysis. In the era of synthetic biology, cutting-edge DNA sequencing and gene synthesis technologies have accelerated the development of cell-based biosensors. Here, we summarize current technological advances in whole-cell heavy metal biosensors, including the synthetic biological components (bioparts), sensing and reporter modules, genetic circuits, and chassis cells. We discuss several opportunities for improvement of synthetic cell-based biosensors. First, new functional modules must be discovered in genome databases, and this knowledge must be used to upgrade specific bioparts through molecular engineering. Second, modules must be assembled into functional biosystems in chassis cells. Third, heterogeneity of individual cells in the microbial population must be eliminated. In the perspectives, the development of whole-cell biosensors is also discussed in the aspects of cultivation methods and synthetic cells.

  6. Optical and Scanning electron Microscopy as advanced analysis methods to determine the condition of synthetic geo membranes

    International Nuclear Information System (INIS)

    Soriano Carrillo, J.; Blanco Fernandez, M.; Garcia Calleja, M. A.; Leiro Lopez, A.; Mateo Sanz, B.; Aguilar Gonzalez, E.; Rubin de Celix, M.

    2014-01-01

    Microscopic techniques have been widely used for years in the study of inorganic materials however their use in organic materials and specifically, in synthetic geo membranes, is very limited. In this study, this innovative technology has been used with the different geo synthetic polymeric barriers with which this research team is experienced: plasticized polyvinyl chloride, polyethylenes, rubbers such as ethenyltriphenyl-diene monomer terpolymer and butyl, polyolefins, ethylene-vinyl acetate copolymer, chlorosulfonated polyethylene and polypropylene. the influence of the extraction area and the time since their application is tested. (Author)

  7. Insights into accelerated liposomal release of topotecan in plasma monitored by a non-invasive fluorescence spectroscopic method

    Science.gov (United States)

    Fugit, Kyle D.; Jyoti, Amar; Upreti, Meenakshi; Anderson, Bradley D.

    2014-01-01

    A non-invasive fluorescence method was developed to monitor liposomal release kinetics of the anticancer agent topotecan (TPT) in physiological fluids and subsequently used to explore the cause of accelerated release in plasma. Analyses of fluorescence excitation spectra confirmed that unencapsulated TPT exhibits a red shift in its spectrum as pH is increased. This property was used to monitor TPT release from actively loaded liposomal formulations having a low intravesicular pH. Mathematical release models were developed to extract reliable rate constants for TPT release in aqueous solutions monitored by fluorescence and release kinetics obtained by HPLC. Using the fluorescence method, accelerated TPT release was observed in plasma as previously reported in the literature. Simulations to estimate the intravesicular pH were conducted to demonstrate that accelerated release correlated with alterations in the low intravesicular pH. This was attributed to the presence of ammonia in plasma samples rather than proteins and other plasma components generally believed to alter release kinetics in physiological samples. These findings shed light on the critical role that ammonia may play in contributing to the preclinical/clinical variability and performance seen with actively-loaded liposomal formulations of TPT and other weakly-basic anticancer agents. PMID:25456833

  8. Influence of tungsten fiber’s slow drift on the measurement of G with angular acceleration method

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Jie; Wu, Wei-Huang; Zhan, Wen-Ze [School of Mechanical Engineering and Electronic Information, China University of Geosciences, Wuhan 430074 (China); Xue, Chao [MOE Key Laboratory of Fundamental Physical Quantities Measurement, School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Physics and Astronomy, Sun Yat-sen University, Guangzhou 510275 (China); Shao, Cheng-Gang, E-mail: cgshao@mail.hust.edu.cn; Wu, Jun-Fei [MOE Key Laboratory of Fundamental Physical Quantities Measurement, School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); Milyukov, Vadim [Sternberg Astronomical Institute, Lomonosov Moscow State University, Moscow 119992 (Russian Federation)

    2016-08-15

    In the measurement of the gravitational constant G with angular acceleration method, the equilibrium position of torsion pendulum with tungsten fiber undergoes a linear slow drift, which results in a quadratic slow drift on the angular velocity of the torsion balance turntable under feedback control unit. The accurate amplitude determination of the useful angular acceleration signal with known frequency is biased by the linear slow drift and the coupling effect of the drifting equilibrium position and the room fixed gravitational background signal. We calculate the influences of the linear slow drift and the complex coupling effect on the value of G, respectively. The result shows that the bias of the linear slow drift on G is 7 ppm, and the influence of the coupling effect is less than 1 ppm.

  9. Application of Microwave Methods for Characterization of NEG Coatings and Obstacle Detection in Accelerator Beam-pipes

    CERN Document Server

    Seebacher, David

    2009-01-01

    In many particle accelerators, including the LHC at the European Organization for Nuclear Research CERN, NEG coatings are used to improve vacuum performance. In other particle accelerators there have been hints that those coatings could have a relevant impact on the beam coupling impedance, however the data available is contradictory. To clarify the possible impact of NEG coatings the electromagnetic properties have been measured. The measurements have been carried out by means of cavity perturbation method. The second part of this thesis deals with the microwave waveguide reflectometer developed at CERN several years ago, which is used as part of the quality assurance test program for the LHC assembly. To ensure optimum operation and to avoid an expensive removal of any foreign object from inside the LHC beam-screen after its completion, microwave reflectometry is performed. Until now several objects have been found by means of reflectometry, but so far neither precise data about the reflections of different...

  10. Detecting sea-level hazards: Simple regression-based methods for calculating the acceleration of sea level

    Science.gov (United States)

    Doran, Kara S.; Howd, Peter A.; Sallenger,, Asbury H.

    2016-01-04

    This report documents the development of statistical tools used to quantify the hazard presented by the response of sea-level elevation to natural or anthropogenic changes in climate and ocean circulation. A hazard is a physical process (or processes) that, when combined with vulnerability (or susceptibility to the hazard), results in risk. This study presents the development and comparison of new and existing sea-level analysis methods, exploration of the strengths and weaknesses of the methods using synthetic time series, and when appropriate, synthesis of the application of the method to observed sea-level time series. These reports are intended to enhance material presented in peer-reviewed journal articles where it is not always possible to provide the level of detail that might be necessary to fully support or recreate published results.

  11. Synthetic environments

    Science.gov (United States)

    Lukes, George E.; Cain, Joel M.

    1996-02-01

    The Advanced Distributed Simulation (ADS) Synthetic Environments Program seeks to create robust virtual worlds from operational terrain and environmental data sources of sufficient fidelity and currency to interact with the real world. While some applications can be met by direct exploitation of standard digital terrain data, more demanding applications -- particularly those support operations 'close to the ground' -- are well-served by emerging capabilities for 'value-adding' by the user working with controlled imagery. For users to rigorously refine and exploit controlled imagery within functionally different workstations they must have a shared framework to allow interoperability within and between these environments in terms of passing image and object coordinates and other information using a variety of validated sensor models. The Synthetic Environments Program is now being expanded to address rapid construction of virtual worlds with research initiatives in digital mapping, softcopy workstations, and cartographic image understanding. The Synthetic Environments Program is also participating in a joint initiative for a sensor model applications programer's interface (API) to ensure that a common controlled imagery exploitation framework is available to all researchers, developers and users. This presentation provides an introduction to ADS and the associated requirements for synthetic environments to support synthetic theaters of war. It provides a technical rationale for exploring applications of image understanding technology to automated cartography in support of ADS and related programs benefitting from automated analysis of mapping, earth resources and reconnaissance imagery. And it provides an overview and status of the joint initiative for a sensor model API.

  12. Electromagnetic Radiation : Variational Methods, Waveguides and Accelerators Including seminal papers of Julian Schwinger

    CERN Document Server

    Milton, Kimball A

    2006-01-01

    This is a graduate level textbook on the theory of electromagnetic radiation and its application to waveguides, transmission lines, accelerator physics and synchrotron radiation. It has grown out of lectures and manuscripts by Julian Schwinger prepared during the war at MIT's Radiation Laboratory, updated with material developed by Schwinger at UCLA in the 1970s and 1980s, and by Milton at the University of Oklahoma since 1994. The book includes a great number of straightforward and challenging exercises and problems. It is addressed to students in physics, electrical engineering, and applied mathematics seeking a thorough introduction to electromagnetism with emphasis on radiation theory and its applications.

  13. Two-Screen Method for Determining Electron Beam Energy and Deflection from Laser Wakefield Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, B B; Ross, J S; Tynan, G R; Divol, L; Glenzer, S H; Leurent, V; Palastro, J P; Ralph, J E; Froula, D H; Clayton, C E; Marsh, K A; Pak, A E; Wang, T L; Joshi, C

    2009-04-24

    Laser Wakefield Acceleration (LWFA) experiments have been performed at the Jupiter Laser Facility, Lawrence Livermore National Laboratory. In order to unambiguously determine the output electron beam energy and deflection angle at the plasma exit, we have implemented a two-screen electron spectrometer. This system is comprised of a dipole magnet followed by two image plates. By measuring the electron beam deviation from the laser axis on each plate, both the energy and deflection angle at the plasma exit are determined through the relativistic equation of motion.

  14. Advanced quadrature sets and acceleration and preconditioning techniques for the discrete ordinates method in parallel computing environments

    Science.gov (United States)

    Longoni, Gianluca

    In the nuclear science and engineering field, radiation transport calculations play a key-role in the design and optimization of nuclear devices. The linear Boltzmann equation describes the angular, energy and spatial variations of the particle or radiation distribution. The discrete ordinates method (S N) is the most widely used technique for solving the linear Boltzmann equation. However, for realistic problems, the memory and computing time require the use of supercomputers. This research is devoted to the development of new formulations for the SN method, especially for highly angular dependent problems, in parallel environments. The present research work addresses two main issues affecting the accuracy and performance of SN transport theory methods: quadrature sets and acceleration techniques. New advanced quadrature techniques which allow for large numbers of angles with a capability for local angular refinement have been developed. These techniques have been integrated into the 3-D SN PENTRAN (Parallel Environment Neutral-particle TRANsport) code and applied to highly angular dependent problems, such as CT-Scan devices, that are widely used to obtain detailed 3-D images for industrial/medical applications. In addition, the accurate simulation of core physics and shielding problems with strong heterogeneities and transport effects requires the numerical solution of the transport equation. In general, the convergence rate of the solution methods for the transport equation is reduced for large problems with optically thick regions and scattering ratios approaching unity. To remedy this situation, new acceleration algorithms based on the Even-Parity Simplified SN (EP-SSN) method have been developed. A new stand-alone code system, PENSSn (Parallel Environment Neutral-particle Simplified SN), has been developed based on the EP-SSN method. The code is designed for parallel computing environments with spatial, angular and hybrid (spatial/angular) domain

  15. Analysis of Samples Treated by Resistance Test Method Exposed to Accelerated Aging

    Directory of Open Access Journals (Sweden)

    Irena Bates

    2015-09-01

    Full Text Available Global awareness that packaging has to be fully adequate and of high quality, is gradually increasing. That is why printing inks and substrates, which have no detrimental effect on packed products, should be considered a compulsory precondition for food and tobacco packaging. Printing inks that have been developed in the recent years, especially for food and tobacco packaging, have low-odour and low migration into the printing substrate during the drying process. Their migration into the printing substrate is within the acceptable limits and has no detrimental effect in terms of food safety. Another extremely important element of prints in high quality food and tobacco packaging is their stability, as they have to be resistant to liquids and chemicals, which are a part of packed product. The selection of an appropriate printing substrate is also extremely relevant, since the interaction of substrate with printing inks should have zero effect on the packed product and should not change the physical appearance of packaging. This paper presents the results of analysing the stability of laboratory samples printed with low-migration inks, observed immediately after the printing (unaged and two treatments of accelerated aging. The accelerated aging of prints was conducted in order to simulate conditions in which food and tobacco packaging can be found due to the prolonged indoors storage. The stability of prints was analysed based on optical characteristics by observing the prints’ relative reflectance curves.

  16. Development of a novel synthetic method for ring construction using organometallic complexes and its application to the total syntheses of natural products.

    Science.gov (United States)

    Mori, Miwako

    2005-05-01

    Organometallic complexes are useful tools in synthetic organic chemistry. We investigated a novel synthetic method for ring construction using organometallic complexes and synthesized natural products and biologically active substances using these methods. Metalacycles formed from an early transition metal and diene, enyne, and diyne are stable under the reaction conditions and they are easily converted into compounds with functional groups by the addition of various agents. We have developed a novel synthetic method of heterocycles from enyne and diene using Cp2ZrBu2. The total syntheses of (-)-dendrobine, (+/-)-mecembrane, and (+/-)-mecembrine were achieved using this procedure. To synthesize these natural products as a chiral form, a novel palladium-catalyzed asymmetric allylic amination was developed, and chiral 2-arylcyclohexenylamine derivatives were synthesized. From these compounds, the total syntheses of (-)-mesembrane, (-)-mesembrine, (+)-crinamine, (-)-haemanthidine, and (+)-pretazetine were achieved. By further development of this procedure, a chiral 2-siloxymethylcyclohexenylamine derivative could be synthesized and the novel synthesis of indole derivatives was developed from this compound. From this indole derivative, (-)-tsubifoline and (-)-strychnine were synthesized.

  17. Photometric and Colorimetric Assessment of LED Chip Scale Packages by Using a Step-Stress Accelerated Degradation Test (SSADT) Method.

    Science.gov (United States)

    Qian, Cheng; Fan, Jiajie; Fang, Jiayi; Yu, Chaohua; Ren, Yi; Fan, Xuejun; Zhang, Guoqi

    2017-10-16

    By solving the problem of very long test time on reliability qualification for Light-emitting Diode (LED) products, the accelerated degradation test with a thermal overstress at a proper range is regarded as a promising and effective approach. For a comprehensive survey of the application of step-stress accelerated degradation test (SSADT) in LEDs, the thermal, photometric, and colorimetric properties of two types of LED chip scale packages (CSPs), i.e., 4000 °K and 5000 °K samples each of which was driven by two different levels of currents (i.e., 120 mA and 350 mA, respectively), were investigated under an increasing temperature from 55 °C to 150 °C and a systemic study of driving current effect on the SSADT results were also reported in this paper. During SSADT, junction temperatures of the test samples have a positive relationship with their driving currents. However, the temperature-voltage curve, which represents the thermal resistance property of the test samples, does not show significant variance as long as the driving current is no more than the sample's rated current. But when the test sample is tested under an overdrive current, its temperature-voltage curve is observed as obviously shifted to the left when compared to that before SSADT. Similar overdrive current affected the degradation scenario is also found in the attenuation of Spectral Power Distributions (SPDs) of the test samples. As used in the reliability qualification, SSADT provides explicit scenes on color shift and correlated color temperature (CCT) depreciation of the test samples, but not on lumen maintenance depreciation. It is also proved that the varying rates of the color shift and CCT depreciation failures can be effectively accelerated with an increase of the driving current, for instance, from 120 mA to 350 mA. For these reasons, SSADT is considered as a suitable accelerated test method for qualifying these two failure modes of LED CSPs.

  18. The normalized weighting factor method: A novel technique for accelerating the convergence of high-resolution convective schemes

    Energy Technology Data Exchange (ETDEWEB)

    Darwish, M.D.; Moukalled, F. [American Univ. of Beirut (Lebanon). Dept. of Mechanical Engineering

    1996-09-01

    This article deals with the development of a new method for accelerating the solution of flow problems discretized using high-resolution convective schemes. The technique is based on the normalized variable and space formulation (NVSF) methodology and is denoted here by the normalized weighting-factor (NWF) method. In contrast with the well-known deferred-correction (DC) procedure, the NWF method is fully implicit and is derived by directly replacing the control-volume face values by their functional relationships in the discretized equation. The direct substitution is performed by the introduction of a variable, NWF, that accounts for the multiplicity of interpolation profiles in HR schemes. The new method is compared with the widely used DC procedure and is shown to be, on average, four times faster.

  19. Non-LTE line-blanketed model atmospheres of hot stars. 1: Hybrid complete linearization/accelerated lambda iteration method

    Science.gov (United States)

    Hubeny, I.; Lanz, T.

    1995-01-01

    A new munerical method for computing non-Local Thermodynamic Equilibrium (non-LTE) model stellar atmospheres is presented. The method, called the hybird complete linearization/accelerated lambda iretation (CL/ALI) method, combines advantages of both its constituents. Its rate of convergence is virtually as high as for the standard CL method, while the computer time per iteration is almost as low as for the standard ALI method. The method is formulated as the standard complete lineariation, the only difference being that the radiation intensity at selected frequency points is not explicity linearized; instead, it is treated by means of the ALI approach. The scheme offers a wide spectrum of options, ranging from the full CL to the full ALI method. We deonstrate that the method works optimally if the majority of frequency points are treated in the ALI mode, while the radiation intensity at a few (typically two to 30) frequency points is explicity linearized. We show how this method can be applied to calculate metal line-blanketed non-LTE model atmospheres, by using the idea of 'superlevels' and 'superlines' introduced originally by Anderson (1989). We calculate several illustrative models taking into accont several tens of thosands of lines of Fe III to Fe IV and show that the hybrid CL/ALI method provides a robust method for calculating non-LTE line-blanketed model atmospheres for a wide range of stellar parameters. The results for individual stellar types will be presented in subsequent papers in this series.

  20. Neutron source, linear-accelerator fuel enricher and regenerator and associated methods

    International Nuclear Information System (INIS)

    Grand, P.; Kouts, H.; Powell, J.R.; Steinberg, M.; Takahashi, H.

    1982-01-01

    A device for producing fissile material inside of fabricated nuclear elements so that they can be used to produce power in nuclear power reactors. Fuel elements, for example, of a lwr are placed in pressure tubes in a vessel surrounding a liquid lead bismuth flowing columnar target. A linear-accelerator proton beam enters the side of the vessel and impinges on the dispersed liquid lead-bismuth columns and produces neutrons which radiate through the surrounding pressure tube assembly or blanket containing the nuclear fuel elements. These neutrons are absorbed by the natural fertile uranium-238 elements and are transformed to fissile plutonium-239. The fertile fuel is thus enriched in fissile material to a concentration whereby they can be used in power reactors. After use in the power reactors, dispensed depleted fuel elements can be reinserted into the pressure tubes surrounding the target and the nuclear fuel regenerated for further burning in the power reactor

  1. Synthetic Rutile

    International Nuclear Information System (INIS)

    Burastero, J.

    1975-01-01

    This work is about the laboratory scale investigation of the conditions in the rutile synthetic production from one me nita in Aguas Dulces reservoir. The iron mineral is chlorinated and volatilized selectively leaving a residue enriched in titanium dioxide which can be used as a substitute of rutile mineral

  2. The development of a method to measure head acceleration and motion in high-impact crashes.

    Science.gov (United States)

    Olvey, Stephen E; Knox, Ted; Cohn, Kelly A

    2004-03-01

    To establish a mechanism to obtain precise measurements of the accelerations of the head in the high-speed racing environment and during crash impacts. The long-term goal is to apply this system to the assessment of head injury in automobile racing drivers and then in participants in other helmeted sports. A multidisciplinary team conceptualized, designed, and successfully tested a triaxial accelerometer system capable of measuring head acceleration and motion in high-impact crashes. The system has been implemented successfully in the professional racing environment. Accurate and reproducible data have been obtained from the accelerometer system in tests on manikins and cadavers and in actual racing events. The system has been implemented in two professional racing series in 2003. Information gained from the accelerometer system is currently being entered into a database. Eventually, the data should aid in the development of improved cockpit head protection in racing cars. Improved helmet design not only in motor sports but also in other helmeted sports should benefit from the data collected. These data will also aid the development of improved head injury protection in military aircraft and passenger vehicles. Although there has been a significant decrease in the overall rate of injury during the past 25 years, head injury remains a serious safety concern in motor sports and the greatest cause of death. Sports-related head injuries are also of great concern because repeated mild head injury has become an important health issue with potential long-term disability. True human tolerance to brain injury has yet to be established. Our scientific knowledge of brain injury is currently based on results derived from manikin, cadaver, and human volunteer testing, along with animal and computer models. The racing environment represents a venue to ethically measure and evaluate the forces involved in human brain injury.

  3. Synthetic torpor: A method for safely and practically transporting experimental animals aboard spaceflight missions to deep space

    Science.gov (United States)

    Griko, Yuri; Regan, Matthew D.

    2018-02-01

    Animal research aboard the Space Shuttle and International Space Station has provided vital information on the physiological, cellular, and molecular effects of spaceflight. The relevance of this information to human spaceflight is enhanced when it is coupled with information gleaned from human-based research. As NASA and other space agencies initiate plans for human exploration missions beyond low Earth orbit (LEO), incorporating animal research into these missions is vitally important to understanding the biological impacts of deep space. However, new technologies will be required to integrate experimental animals into spacecraft design and transport them beyond LEO in a safe and practical way. In this communication, we propose the use of metabolic control technologies to reversibly depress the metabolic rates of experimental animals while in transit aboard the spacecraft. Compared to holding experimental animals in active metabolic states, the advantages of artificially inducing regulated, depressed metabolic states (called synthetic torpor) include significantly reduced mass, volume, and power requirements within the spacecraft owing to reduced life support requirements, and mitigated radiation- and microgravity-induced negative health effects on the animals owing to intrinsic physiological properties of torpor. In addition to directly benefitting animal research, synthetic torpor-inducing systems will also serve as test beds for systems that may eventually hold human crewmembers in similar metabolic states on long-duration missions. The technologies for inducing synthetic torpor, which we discuss, are at relatively early stages of development, but there is ample evidence to show that this is a viable idea and one with very real benefits to spaceflight programs. The increasingly ambitious goals of world's many spaceflight programs will be most quickly and safely achieved with the help of animal research systems transported beyond LEO; synthetic torpor may

  4. Programming languages for synthetic biology.

    Science.gov (United States)

    Umesh, P; Naveen, F; Rao, Chanchala Uma Maheswara; Nair, Achuthsankar S

    2010-12-01

    In the backdrop of accelerated efforts for creating synthetic organisms, the nature and scope of an ideal programming language for scripting synthetic organism in-silico has been receiving increasing attention. A few programming languages for synthetic biology capable of defining, constructing, networking, editing and delivering genome scale models of cellular processes have been recently attempted. All these represent important points in a spectrum of possibilities. This paper introduces Kera, a state of the art programming language for synthetic biology which is arguably ahead of similar languages or tools such as GEC, Antimony and GenoCAD. Kera is a full-fledged object oriented programming language which is tempered by biopart rule library named Samhita which captures the knowledge regarding the interaction of genome components and catalytic molecules. Prominent feature of the language are demonstrated through a toy example and the road map for the future development of Kera is also presented.

  5. [An ultrafast liquid chromatography-tandem mass spectrometric method for simultaneous determination of common artificial synthetic pigments in cooked meat products].

    Science.gov (United States)

    Chen, Xiaohong; Li, Xiaoping; Zhao, Yonggang; Pan, Shengdong; Jin, Micong

    2015-07-01

    A method based on ultrafast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) has been developed for the simultaneous determination of seven synthetic pigments in cooked meat product. After the cooked meat products were extracted by mixed extraction agent, purified by WAX column, the UFLC separation was performed on a Shim-pack XR-ODS II column (75 mm x 2.0 mm, 2.2 µm) with a linear gradient elution program of acetonitrile and ammonium acetate (AmAc, 5 mmol/L) as the mobile phase. Electrospray ionization was applied and operated in the negative ion mode. The limits of quantitation (LOQs) for the seven synthetic pigments were in the range of 0.7-5.0 µg/kg. The calibration curves showed good linearities for the seven analytes in their detection ranges, and the correlative coefficients (r) were more than 0.999. The recoveries were between 88.2%-106.5% with the RSDs in the range of 1.2%-5.0%. The method is sensitive, reproducible, quick and adapts to the simultaneous determination of the seven synthetic pigments in cooked meat product.

  6. Electrochemical characteristics of silver- and nickel-coated synthetic graphite prepared by a gas suspension spray coating method for the anode of lithium secondary batteries

    International Nuclear Information System (INIS)

    Choi, Won Chang; Byun, Dongjin; Lee, Joong Kee; Cho, Byung won

    2004-01-01

    Four kinds of synthetic graphite coated with silver and nickel for the anodes of lithium secondary batteries were prepared by a gas suspension spray coating method. The electrode coated with silver showed higher charge-discharge capacities due to a Ag-Li alloy, but rate capability decreased at higher charge-discharge rate. This result can be explained by the formation of an artificial Ag oxidation film with higher impedance, this lowered the rate capability at high charge-discharge rate due to its low electrical conductivity. Rate capability is improved, however, by coating nickel and silver together on the surface of synthetic graphite. The nickel which is inactive with oxidation reaction plays an important role as a conducting agent which enhanced the conductivity of the electrode

  7. A comparison of different quasi-newton acceleration methods for partitioned multi-physics codes

    CSIR Research Space (South Africa)

    Haelterman, R

    2018-02-01

    Full Text Available ) and Switched Column-Updating Method (SCU) 1. The Column-Updating method is a quasi-Newton method that was introduced by Martinez [25, 27, 28]. The rank-one update of this method is such that the column of the approximate Jacobian corresponding to the largest...K,s = Argmax{|〈ı j,δxs〉|; j = 1, . . . ,mn}. (Kˆ′1) −1 is typically set to be −I, 2. The Inverse Column-Updating method (ICU) is a quasi-Newton method that was introduced by Martinez and Zambaldi [23, 26]. It uses a rank-one update such that the column...

  8. Half-range acceleration for one-dimensional transport problems

    International Nuclear Information System (INIS)

    Zika, M.R.; Larsen, E.W.

    1998-01-01

    Researchers have devoted considerable effort to developing acceleration techniques for transport iterations in highly diffusive problems. The advantages and disadvantages of source iteration, rebalance, diffusion synthetic acceleration (DSA), transport synthetic acceleration (TSA), and projection acceleration methods are documented in the literature and will not be discussed here except to note that no single method has proven to be applicable to all situations. Here, the authors describe a new acceleration method that is based solely on transport sweeps, is algebraically linear (and is therefore amenable to a Fourier analysis), and yields a theoretical spectral radius bounded by one-third for all cases. This method does not introduce spatial differencing difficulties (as is the case for DSA) nor does its theoretical performance degrade as a function of mesh and material properties (as is the case for TSA). Practical simulations of the new method agree with the theoretical predictions, except for scattering ratios very close to unity. At this time, they believe that the discrepancy is due to the effect of boundary conditions. This is discussed further

  9. Click chemistry approach to conventional vegetable tanning process: accelerated method with improved organoleptic properties.

    Science.gov (United States)

    Krishnamoorthy, Ganesan; Ramamurthy, Govindaswamy; Sadulla, Sayeed; Sastry, Thotapalli Parvathaleswara; Mandal, Asit Baran

    2014-09-01

    Click chemistry approaches are tailored to generate molecular building blocks quickly and reliably by joining small units together selectively and covalently, stably and irreversibly. The vegetable tannins such as hydrolyzable and condensed tannins are capable to produce rather stable radicals or inhibit the progress of radicals and are prone to oxidations such as photo and auto-oxidation, and their anti-oxidant nature is well known. A lot remains to be done to understand the extent of the variation of leather stability, color variation (lightening and darkening reaction of leather), and poor resistance to water uptake for prolonged periods. In the present study, we have reported click chemistry approaches to accelerated vegetable tanning processes based on periodates catalyzed formation of oxidized hydrolysable and condensed tannins for high exhaustion with improved properties. The distribution of oxidized vegetable tannin, the thermal stability such as shrinkage temperature (T s) and denaturation temperature (T d), resistance to collagenolytic activities, and organoleptic properties of tanned leather as well as the evaluations of eco-friendly characteristics were investigated. Scanning electron microscopic analysis indicates the cross section of tightness of the leather. Differential scanning calorimetric analysis shows that the T d of leather is more than that of vegetable tanned or equal to aldehyde tanned one. The leathers exhibited fullness, softness, good color, and general appearance when compared to non-oxidized vegetable tannin. The developed process benefits from significant reduction in total solids and better biodegradability in the effluent, compared to non-oxidized vegetable tannins.

  10. Accelerating the explicitly restarted Arnoldi method with GPUs using an auto-tuned matrix vector product

    International Nuclear Information System (INIS)

    Dubois, J.; Calvin, Ch.; Dubois, J.; Petiton, S.

    2011-01-01

    This paper presents a parallelized hybrid single-vector Arnoldi algorithm for computing approximations to Eigen-pairs of a nonsymmetric matrix. We are interested in the use of accelerators and multi-core units to speed up the Arnoldi process. The main goal is to propose a parallel version of the Arnoldi solver, which can efficiently use multiple multi-core processors or multiple graphics processing units (GPUs) in a mixed coarse and fine grain fashion. In the proposed algorithms, this is achieved by an auto-tuning of the matrix vector product before starting the Arnoldi Eigen-solver as well as the reorganization of the data and global communications so that communication time is reduced. The execution time, performance, and scalability are assessed with well-known dense and sparse test matrices on multiple Nehalems, GT200 NVidia Tesla, and next generation Fermi Tesla. With one processor, we see a performance speedup of 2 to 3x when using all the physical cores, and a total speedup of 2 to 8x when adding a GPU to this multi-core unit, and hence a speedup of 4 to 24x compared to the sequential solver. (authors)

  11. Acceleration of the AFEN method by two-node nonlinear iteration

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Kap Suk; Cho, Nam Zin; Noh, Jae Man; Hong, Ser Gi [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-12-31

    A nonlinear iterative scheme developed to reduce the computing time of the AFEN method was tested and applied to two benchmark problems. The new nonlinear method for the AFEN method is based on solving two-node problems and use of two nonlinear correction factors at every interface instead of one factor in the conventional scheme. The use of two correction factors provides higher-order accurate interface fluxes as well as currents which are used as the boundary conditions of the two-node problem. The numerical results show that this new method gives exactly the same solution as that of the original AFEN method and the computing time is significantly reduced in comparison with the original AFEN method. 7 refs., 1 fig., 1 tab. (Author)

  12. Does Certification Change the Trajectory of Tree Cover in Working Forests in The Tropics? An Application of the Synthetic Control Method of Impact Evaluation

    Directory of Open Access Journals (Sweden)

    Pushpendra Rana

    2018-02-01

    Full Text Available Certification by the Forest Stewardship Council (FSC remains rare among forest management units (FMUs in natural tropical forests, presenting a challenge for impact evaluation. We demonstrate application of the synthetic control method (SCM to evaluate the impact of FSC certification on a single FMU in each of three tropical forest landscapes. Specifically, we estimate causal effects on tree cover change from the year of certification to 2012 using SCM and open-access, pan-tropical datasets. We demonstrate that it is possible to construct synthetic controls, or weighted combinations of non-certified FMUs, that followed the same path of tree cover change as the certified FMUs before certification. By using these synthetic controls to measure counterfactual tree cover change after certification, we find that certification reduced tree cover loss in the most recent year (2012 in all three landscapes. However, placebo tests show that in one case, this effect was not significant, and in another case, it followed several years in which certification had the opposite effect (increasing tree cover loss. We conclude that SCM has promise for identifying temporally varying impacts of small-N interventions on land use and land cover change.

  13. Computationally efficient methods for modelling laser wakefield acceleration in the blowout regime

    Science.gov (United States)

    Cowan, B. M.; Kalmykov, S. Y.; Beck, A.; Davoine, X.; Bunkers, K.; Lifschitz, A. F.; Lefebvre, E.; Bruhwiler, D. L.; Shadwick, B. A.; Umstadter, D. P.; Umstadter

    2012-08-01

    Electron self-injection and acceleration until dephasing in the blowout regime is studied for a set of initial conditions typical of recent experiments with 100-terawatt-class lasers. Two different approaches to computationally efficient, fully explicit, 3D particle-in-cell modelling are examined. First, the Cartesian code vorpal (Nieter, C. and Cary, J. R. 2004 VORPAL: a versatile plasma simulation code. J. Comput. Phys. 196, 538) using a perfect-dispersion electromagnetic solver precisely describes the laser pulse and bubble dynamics, taking advantage of coarser resolution in the propagation direction, with a proportionally larger time step. Using third-order splines for macroparticles helps suppress the sampling noise while keeping the usage of computational resources modest. The second way to reduce the simulation load is using reduced-geometry codes. In our case, the quasi-cylindrical code calder-circ (Lifschitz, A. F. et al. 2009 Particle-in-cell modelling of laser-plasma interaction using Fourier decomposition. J. Comput. Phys. 228(5), 1803-1814) uses decomposition of fields and currents into a set of poloidal modes, while the macroparticles move in the Cartesian 3D space. Cylindrical symmetry of the interaction allows using just two modes, reducing the computational load to roughly that of a planar Cartesian simulation while preserving the 3D nature of the interaction. This significant economy of resources allows using fine resolution in the direction of propagation and a small time step, making numerical dispersion vanishingly small, together with a large number of particles per cell, enabling good particle statistics. Quantitative agreement of two simulations indicates that these are free of numerical artefacts. Both approaches thus retrieve the physically correct evolution of the plasma bubble, recovering the intrinsic connection of electron self-injection to the nonlinear optical evolution of the driver.

  14. Is oncoplastic surgery a contraindication for accelerated partial breast radiation using the interstitial multicatheter brachytherapy method?

    Science.gov (United States)

    Roth, Anna-Maria; Kauer-Dorner, Daniela; Resch, Alexandra; Schmid, Andreas; Thill, Marc; Niehoff, Peter; Melchert, Corinna; Berger, Daniel; Kovács, György

    2014-01-01

    To evaluate accelerated partial breast irradiation (APBI) in patients after oncoplastic surgery for early breast cancer. A retrospective analysis of 136 breasts of 134 patients, who received breast-conserving oncoplastic surgery for low-risk breast cancer between 2002 and 2010 in the Universities of Vienna and Luebeck followed by adjuvant APBI applying total doses of pulse dose rate of 50.4 Gy or high-dose rate (HDR) of 32 Gy over 4 days. Target volume definition was performed by the use of surgical-free margin data, related to intraoperatively fixed clip positions, pre- and postoperative imaging, and palpation. At the time of data acquisition, 131 of 134 patients were alive. The median follow-up time was 39 months (range, 4-106 months). After high-dose rate treatment, 3 of 89 patients showed systemic progress after a mean follow-up of 47 months (range, 19-75 months) and 2 patients had a different quadrant in-breast tumor after 27 and 35 months. One patient died 7 months after treatment of unknown causes. After pulse dose rate treatment, 1 of 45 patients had a local recurrence after 42 months and 1 patient died because of another cause after 13 months. We observed mild fibrosis in 27 breasts, telangiectasia in 6, hyperpigmentation in 14 cases, and keloid formation in 1. These preliminary results suggest the feasibility of multicatheter APBI after oncoplastic breast-conserving surgery in selected low-risk breast cancer patients; however, special attention to target volume definition is needed. Further prospective investigations with long follow-up are needed to define the real value of the procedure. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  15. Accelerating the SCE-UA Global Optimization Method Based on Multi-Core CPU and Many-Core GPU

    Directory of Open Access Journals (Sweden)

    Guangyuan Kan

    2016-01-01

    Full Text Available The famous global optimization SCE-UA method, which has been widely used in the field of environmental model parameter calibration, is an effective and robust method. However, the SCE-UA method has a high computational load which prohibits the application of SCE-UA to high dimensional and complex problems. In recent years, the hardware of computer, such as multi-core CPUs and many-core GPUs, improves significantly. These much more powerful new hardware and their software ecosystems provide an opportunity to accelerate the SCE-UA method. In this paper, we proposed two parallel SCE-UA methods and implemented them on Intel multi-core CPU and NVIDIA many-core GPU by OpenMP and CUDA Fortran, respectively. The Griewank benchmark function was adopted in this paper to test and compare the performances of the serial and parallel SCE-UA methods. According to the results of the comparison, some useful advises were given to direct how to properly use the parallel SCE-UA methods.

  16. Planetary method to measure the neutrons spectrum in lineal accelerators of medical use; Metodo planetario para medir el espectro de neutrones en aceleradores lineales de uso medico

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Benites R, J. L., E-mail: fermineutron@yahoo.com [Centro Estatal de Cancerologia de Nayarit, Servicio de Seguridad Radiologica, Calzada de la Cruz 118 Sur, 63000 Tepic, Nayarit (Mexico)

    2014-08-15

    A novel procedure to measure the neutrons spectrum originated in a lineal accelerator of medical use has been developed. The method uses a passive spectrometer of Bonner spheres. The main advantage of the method is that only requires of a single shot of the accelerator. When this is used around a lineal accelerator is necessary to operate it under the same conditions so many times like the spheres that contain the spectrometer, activity that consumes enough time. The developed procedure consists on situating all the spheres of the spectrometer at the same time and to realize the reading making a single shot. With this method the photo neutrons spectrum produced by a lineal accelerator Varian ix of 15 MV to 100 cm of the isocenter was determined, with the spectrum is determined the total flow and the ambient dose equivalent. (Author)

  17. EXPERIMENTAL AND ANALYTICAL METHOD FOR ACCELERATED FATIGUE BENCH TEST OF STRUCTURES AT REGULAR MULTI-CYCLE LOADING

    Directory of Open Access Journals (Sweden)

    E. K. Pochtenny

    2006-01-01

    Full Text Available The paper presents main statements of the developed general scientific principles and experimental and analytical method for accelerated bench test of bearing structures and machine parts at a regular loading. According to the test results executed in terms of the proposed methodology it is possible to predict a service life of a number of automotive bearing structures for conditions of irregular loading.The developed method has been used for execution of bench tests and calculation and experimental estimation of a service life of a truck tractor frame, prospective types of axles and elements of trailer train suspension and other bearing structures of automotive machinery of the Minsk Motor-Works.

  18. Development of an extraction method for the determination of dissolved organic radiocarbon in seawater by accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Tanaka, Takayuki; Otosaka, Shigeyoshi; Togawa, Orihiko; Amano, Hikaru

    2009-01-01

    We developed an extraction method for accurately and reproducibly determining dissolved organic radiocarbon in seawater by ultraviolet oxidation of dissolved organic carbon and subsequent accelerator mass spectrometry. We determined the irradiation time required for oxidation of the dissolved organic carbon. By modifying the experimental apparatus, we decreased contamination by dead carbon, which came mainly from petrochemical products in the apparatus and from the incursion of carbon dioxide from the atmosphere. The modifications decreased the analytical blank level to less than 1% of sample size, a percentage that had not previously been achieved. The recovery efficiency was high, 95±1%. To confirm both the accuracy and reproducibility of the method, we tested it by analyzing an oxalic acid radiocarbon reference material and by determining the dissolved organic carbon in surface seawater samples. (author)

  19. Using combinatorial bioinformatics methods to analyze annual perspective changes of influenza viruses and to accelerate development of effective vaccines

    Directory of Open Access Journals (Sweden)

    Yu-Jen Hu

    2015-08-01

    Full Text Available The standard World Health Organization procedure for vaccine development has provided a guideline for influenza viruses, but no systematic operational model. We recently designed a systemic analysis method to evaluate annual perspective sequence changes of influenza virus strains. We applied dnaml of PHYLIP 3.69, developed by Joseph Felsenstein of Washington University, and ClustalX2, developed by Larkin et al, for calculating, comparing, and localizing the most plausible vaccine epitopes. This study identified the changes in biological sequences and associated alignment alterations, which would ultimately affect epitope structures, as well as the plausible hidden features to search for the most conserved and effective epitopes for vaccine development. Addition our newly designed systemic analysis method to supplement the WHO guidelines could accelerate the development of urgently needed vaccines that might concurrently combat several strains of viruses within a shorter period.

  20. Photometric and Colorimetric Assessment of LED Chip Scale Packages by Using a Step-Stress Accelerated Degradation Test (SSADT Method

    Directory of Open Access Journals (Sweden)

    Cheng Qian

    2017-10-01

    Full Text Available By solving the problem of very long test time on reliability qualification for Light-emitting Diode (LED products, the accelerated degradation test with a thermal overstress at a proper range is regarded as a promising and effective approach. For a comprehensive survey of the application of step-stress accelerated degradation test (SSADT in LEDs, the thermal, photometric, and colorimetric properties of two types of LED chip scale packages (CSPs, i.e., 4000 °K and 5000 °K samples each of which was driven by two different levels of currents (i.e., 120 mA and 350 mA, respectively, were investigated under an increasing temperature from 55 °C to 150 °C and a systemic study of driving current effect on the SSADT results were also reported in this paper. During SSADT, junction temperatures of the test samples have a positive relationship with their driving currents. However, the temperature-voltage curve, which represents the thermal resistance property of the test samples, does not show significant variance as long as the driving current is no more than the sample’s rated current. But when the test sample is tested under an overdrive current, its temperature-voltage curve is observed as obviously shifted to the left when compared to that before SSADT. Similar overdrive current affected the degradation scenario is also found in the attenuation of Spectral Power Distributions (SPDs of the test samples. As used in the reliability qualification, SSADT provides explicit scenes on color shift and correlated color temperature (CCT depreciation of the test samples, but not on lumen maintenance depreciation. It is also proved that the varying rates of the color shift and CCT depreciation failures can be effectively accelerated with an increase of the driving current, for instance, from 120 mA to 350 mA. For these reasons, SSADT is considered as a suitable accelerated test method for qualifying these two failure modes of LED CSPs.

  1. A Synthetic Method for Atmospheric Diffusion Simulation and Environmental Impact Assessment of Accidental Pollution in the Chemical Industry in a WEBGIS Context

    Directory of Open Access Journals (Sweden)

    Haochen Ni

    2014-09-01

    Full Text Available The chemical industry poses a potential security risk to factory personnel and neighboring residents. In order to mitigate prospective damage, a synthetic method must be developed for an emergency response. With the development of environmental numeric simulation models, model integration methods, and modern information technology, many Decision Support Systems (DSSs have been established. However, existing systems still have limitations, in terms of synthetic simulation and network interoperation. In order to resolve these limitations, the matured simulation model for chemical accidents was integrated into the WEB Geographic Information System (WEBGIS platform. The complete workflow of the emergency response, including raw data (meteorology information, and accident information management, numeric simulation of different kinds of accidents, environmental impact assessments, and representation of the simulation results were achieved. This allowed comprehensive and real-time simulation of acute accidents in the chemical industry. The main contribution of this paper is that an organizational mechanism of the model set, based on the accident type and pollutant substance; a scheduling mechanism for the parallel processing of multi-accident-type, multi-accident-substance, and multi-simulation-model; and finally a presentation method for scalar and vector data on the web browser on the integration of a WEB Geographic Information System (WEBGIS platform. The outcomes demonstrated that this method could provide effective support for deciding emergency responses of acute chemical accidents.

  2. A synthetic method for atmospheric diffusion simulation and environmental impact assessment of accidental pollution in the chemical industry in a WEBGIS context.

    Science.gov (United States)

    Ni, Haochen; Rui, Yikang; Wang, Jiechen; Cheng, Liang

    2014-09-05

    The chemical industry poses a potential security risk to factory personnel and neighboring residents. In order to mitigate prospective damage, a synthetic method must be developed for an emergency response. With the development of environmental numeric simulation models, model integration methods, and modern information technology, many Decision Support Systems (DSSs) have been established. However, existing systems still have limitations, in terms of synthetic simulation and network interoperation. In order to resolve these limitations, the matured simulation model for chemical accidents was integrated into the WEB Geographic Information System (WEBGIS) platform. The complete workflow of the emergency response, including raw data (meteorology information, and accident information) management, numeric simulation of different kinds of accidents, environmental impact assessments, and representation of the simulation results were achieved. This allowed comprehensive and real-time simulation of acute accidents in the chemical industry. The main contribution of this paper is that an organizational mechanism of the model set, based on the accident type and pollutant substance; a scheduling mechanism for the parallel processing of multi-accident-type, multi-accident-substance, and multi-simulation-model; and finally a presentation method for scalar and vector data on the web browser on the integration of a WEB Geographic Information System (WEBGIS) platform. The outcomes demonstrated that this method could provide effective support for deciding emergency responses of acute chemical accidents.

  3. GPGPU accelerated Krylov methods for compact modeling of on-chip passive integrated structures within the Chameleon-RF workflow

    Directory of Open Access Journals (Sweden)

    Sebastian Gim

    2012-11-01

    Full Text Available Continued device scaling into the nanometer region and high frequencies of operation well into the multi-GHz region has given rise to new effects that previously had negligible impact but now present greater challenges and unprecedented complexity to designing successful mixed-signal silicon. The Chameleon-RF project was conceived to address these challenges. Creative use of domain decomposition, multi grid techniques or reduced order modeling techniques (ROM can be selectively applied at all levels of the process to efficiently prune down degrees of freedom (DoFs. However, the simulation of complex systems within a reasonable amount of time remains a computational challenge. This paper presents work done in the incorporation of GPGPU technology to accelerate Krylov based algorithms used for compact modeling of on-chip passive integrated structures within the workflow of the Chameleon-RF project. Based upon insight gained from work done above, a novel GPGPU accelerated algorithm was developed for the Krylov ROM (kROM methods and is described here for the benefit of the wider community.

  4. Synthetic Metabolic Pathways

    DEFF Research Database (Denmark)

    topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Synthetic Metabolic Pathways: Methods and Protocols aims to ensure successful results in the further study...

  5. Synthetic growth reference charts

    NARCIS (Netherlands)

    Hermanussen, Michael; Stec, Karol; Aßmann, Christian; Meigen, Christof; Van Buuren, Stef

    2016-01-01

    Objectives: To reanalyze the between-population variance in height, weight, and body mass index (BMI), and to provide a globally applicable technique for generating synthetic growth reference charts. Methods: Using a baseline set of 196 female and 197 male growth studies published since 1831, common

  6. Synthetic Aperture Sequential Beamforming

    DEFF Research Database (Denmark)

    Kortbek, Jacob; Jensen, Jørgen Arendt; Gammelmark, Kim Løkke

    2008-01-01

    A synthetic aperture focusing (SAF) technique denoted Synthetic Aperture Sequential Beamforming (SASB) suitable for 2D and 3D imaging is presented. The technique differ from prior art of SAF in the sense that SAF is performed on pre-beamformed data contrary to channel data. The objective...... is stored. The second stage applies the focused image lines from the first stage as input data. The SASB method has been investigated using simulations in Field II and by off-line processing of data acquired with a commercial scanner. The performance of SASB with a static image object is compared with DRF...

  7. Can Accelerators Accelerate Learning?

    International Nuclear Information System (INIS)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-01-01

    The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ)[1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

  8. GPU accelerated Discrete Element Method (DEM) molecular dynamics for conservative, faceted particle simulations

    Energy Technology Data Exchange (ETDEWEB)

    Spellings, Matthew [Chemical Engineering, University of Michigan, 2800 Plymouth Rd., Ann Arbor, MI 48109 (United States); Biointerfaces Institute, University of Michigan, 2800 Plymouth Rd., Ann Arbor, MI 48109 (United States); Marson, Ryan L. [Materials Science & Engineering, University of Michigan, 2300 Hayward St., Ann Arbor, MI 48109 (United States); Biointerfaces Institute, University of Michigan, 2800 Plymouth Rd., Ann Arbor, MI 48109 (United States); Anderson, Joshua A. [Chemical Engineering, University of Michigan, 2800 Plymouth Rd., Ann Arbor, MI 48109 (United States); Biointerfaces Institute, University of Michigan, 2800 Plymouth Rd., Ann Arbor, MI 48109 (United States); Glotzer, Sharon C., E-mail: sglotzer@umich.edu [Chemical Engineering, University of Michigan, 2800 Plymouth Rd., Ann Arbor, MI 48109 (United States); Materials Science & Engineering, University of Michigan, 2300 Hayward St., Ann Arbor, MI 48109 (United States); Biointerfaces Institute, University of Michigan, 2800 Plymouth Rd., Ann Arbor, MI 48109 (United States)

    2017-04-01

    Faceted shapes, such as polyhedra, are commonly found in systems of nanoscale, colloidal, and granular particles. Many interesting physical phenomena, like crystal nucleation and growth, vacancy motion, and glassy dynamics are challenging to model in these systems because they require detailed dynamical information at the individual particle level. Within the granular materials community the Discrete Element Method has been used extensively to model systems of anisotropic particles under gravity, with friction. We provide an implementation of this method intended for simulation of hard, faceted nanoparticles, with a conservative Weeks–Chandler–Andersen (WCA) interparticle potential, coupled to a thermodynamic ensemble. This method is a natural extension of classical molecular dynamics and enables rigorous thermodynamic calculations for faceted particles.

  9. GPU accelerated Discrete Element Method (DEM) molecular dynamics for conservative, faceted particle simulations

    Science.gov (United States)

    Spellings, Matthew; Marson, Ryan L.; Anderson, Joshua A.; Glotzer, Sharon C.

    2017-04-01

    Faceted shapes, such as polyhedra, are commonly found in systems of nanoscale, colloidal, and granular particles. Many interesting physical phenomena, like crystal nucleation and growth, vacancy motion, and glassy dynamics are challenging to model in these systems because they require detailed dynamical information at the individual particle level. Within the granular materials community the Discrete Element Method has been used extensively to model systems of anisotropic particles under gravity, with friction. We provide an implementation of this method intended for simulation of hard, faceted nanoparticles, with a conservative Weeks-Chandler-Andersen (WCA) interparticle potential, coupled to a thermodynamic ensemble. This method is a natural extension of classical molecular dynamics and enables rigorous thermodynamic calculations for faceted particles.

  10. An accelerated hybrid TLM-IE method for the investigation of shielding effectiveness

    Directory of Open Access Journals (Sweden)

    N. Fichtner

    2010-09-01

    Full Text Available A hybrid numerical technique combining time-domain integral equations (TD-IE with the transmission line matrix (TLM method is presented for the efficient modeling of transient wave phenomena. This hybrid method allows the full-wave modeling of circuits in the time-domain as well as the electromagnetic coupling of remote TLM subdomains using integral equations (IE. By using the integral equations the space between the TLM subdomains is not discretized and consequently doesn't contribute to the computational effort. The cost for the evaluation of the time-domain integral equations (TD-IE is further reduced using a suitable plane-wave representation of the source terms. The hybrid TD-IE/TLM method is applied in the computation of the shielding effectiveness (SE of metallic enclosures.

  11. Imaging method for downward-looking sparse linear array three-dimensional synthetic aperture radar based on reweighted atomic norm

    Science.gov (United States)

    Bao, Qian; Han, Kuoye; Lin, Yun; Zhang, Bingchen; Liu, Jianguo; Hong, Wen

    2016-01-01

    We propose an imaging algorithm for downward-looking sparse linear array three-dimensional synthetic aperture radar (DLSLA 3-D SAR) in the circumstance of cross-track sparse and nonuniform array configuration. Considering the off-grid effect and the resolution improvement, the algorithm combines pseudo-polar formatting algorithm, reweighed atomic norm minimization (RANM), and a parametric relaxation-based cyclic approach (RELAX) to improve the imaging performance with a reduced number of array antennas. RANM is employed in the cross-track imaging after pseudo-polar formatting the DLSLA 3-D SAR echo signal, then the reconstructed results are refined by RELAX. By taking advantage of the reweighted scheme, RANM can improve the resolution of the atomic norm minimization, and outperforms discretized compressive sensing schemes that suffer from off-grid effect. The simulated and real data experiments of DLSLA 3-D SAR verify the performance of the proposed algorithm.

  12. Properties of the Feynman-alpha method applied to accelerator-driven subcritical systems.

    Science.gov (United States)

    Taczanowski, S; Domanska, G; Kopec, M; Janczyszyn, J

    2005-01-01

    A Monte Carlo study of the Feynman-method with a simple code simulating the multiplication chain, confined to pertinent time-dependent phenomena has been done. The significance of its key parameters (detector efficiency and dead time, k-source and spallation neutrons multiplicities, required number of fissions etc.) has been discussed. It has been demonstrated that this method can be insensitive to properties of the zones surrounding the core, whereas is strongly affected by the detector dead time. In turn, the influence of harmonics in the neutron field and of the dispersion of spallation neutrons has proven much less pronounced.

  13. A GPU-accelerated semi-implicit fractional step method for numerical solutions of incompressible Navier-Stokes equations

    Science.gov (United States)

    Ha, Sanghyun; Park, Junshin; You, Donghyun

    2017-11-01

    Utility of the computational power of modern Graphics Processing Units (GPUs) is elaborated for solutions of incompressible Navier-Stokes equations which are integrated using a semi-implicit fractional-step method. Due to its serial and bandwidth-bound nature, the present choice of numerical methods is considered to be a good candidate for evaluating the potential of GPUs for solving Navier-Stokes equations using non-explicit time integration. An efficient algorithm is presented for GPU acceleration of the Alternating Direction Implicit (ADI) and the Fourier-transform-based direct solution method used in the semi-implicit fractional-step method. OpenMP is employed for concurrent collection of turbulence statistics on a CPU while Navier-Stokes equations are computed on a GPU. Extension to multiple NVIDIA GPUs is implemented using NVLink supported by the Pascal architecture. Performance of the present method is experimented on multiple Tesla P100 GPUs compared with a single-core Xeon E5-2650 v4 CPU in simulations of boundary-layer flow over a flat plate. Supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (Ministry of Science, ICT and Future Planning NRF-2016R1E1A2A01939553, NRF-2014R1A2A1A11049599, and Ministry of Trade, Industry and Energy 201611101000230).

  14. Accelerated gradient methods for total-variation-based CT image reconstruction

    DEFF Research Database (Denmark)

    Jørgensen, Jakob Heide; Jensen, Tobias Lindstrøm; Hansen, Per Christian

    2011-01-01

    incorporates several heuristics from the optimization literature such as Barzilai-Borwein (BB) step size selection and nonmonotone line search. The latter uses a cleverly chosen sequence of auxiliary points to achieve a better convergence rate. The methods are memory efficient and equipped with a stopping...

  15. GPU acceleration of the stochastic grid bundling method for early-exercise options

    NARCIS (Netherlands)

    A. Leitao Rodriguez (Álvaro); C.W. Oosterlee (Cornelis)

    2015-01-01

    htmlabstractIn this work, a parallel graphics processing units (GPU) version of the Monte Carlo stochastic grid bundling method (SGBM) for pricing multi-dimensional early-exercise options is presented. To extend the method’s applicability, the problem dimensions and the number of bundles will be

  16. ACCELERATION RENDERING METHOD ON RAY TRACING WITH ANGLE COMPARISON AND DISTANCE COMPARISON

    Directory of Open Access Journals (Sweden)

    Liliana liliana

    2007-01-01

    Full Text Available In computer graphics applications, to produce realistic images, a method that is often used is ray tracing. Ray tracing does not only model local illumination but also global illumination. Local illumination count ambient, diffuse and specular effects only, but global illumination also count mirroring and transparency. Local illumination count effects from the lamp(s but global illumination count effects from other object(s too. Objects that are usually modeled are primitive objects and mesh objects. The advantage of mesh modeling is various, interesting and real-like shape. Mesh contains many primitive objects like triangle or square (rare. A problem in mesh object modeling is long rendering time. It is because every ray must be checked with a lot of triangle of the mesh. Added by ray from other objects checking, the number of ray that traced will increase. It causes the increasing of rendering time. To solve this problem, in this research, new methods are developed to make the rendering process of mesh object faster. The new methods are angle comparison and distance comparison. These methods are used to reduce the number of ray checking. The rays predicted will not intersect with the mesh, are not checked weather the ray intersects the mesh. With angle comparison, if using small angle to compare, the rendering process will be fast. This method has disadvantage, if the shape of each triangle is big, some triangles will be corrupted. If the angle to compare is bigger, mesh corruption can be avoided but the rendering time will be longer than without comparison. With distance comparison, the rendering time is less than without comparison, and no triangle will be corrupted.

  17. Synthetic Cannabinoids.

    Science.gov (United States)

    Mills, Brooke; Yepes, Andres; Nugent, Kenneth

    2015-07-01

    Synthetic cannabinoids (SCBs), also known under the brand names of "Spice," "K2," "herbal incense," "Cloud 9," "Mojo" and many others, are becoming a large public health concern due not only to their increasing use but also to their unpredictable toxicity and abuse potential. There are many types of SCBs, each having a unique binding affinity for cannabinoid receptors. Although both Δ-tetrahydrocannabinol (THC) and SCBs stimulate the same receptors, cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2), studies have shown that SCBs are associated with higher rates of toxicity and hospital admissions than is natural cannabis. This is likely due to SCBs being direct agonists of the cannabinoid receptors, whereas THC is a partial agonist. Furthermore, the different chemical structures of SCBs found in Spice or K2 may interact in unpredictable ways to elicit previously unknown, and the commercial products may have unknown contaminants. The largest group of users is men in their 20s who participate in polydrug use. The most common reported toxicities with SCB use based on studies using Texas Poison Control records are tachycardia, agitation and irritability, drowsiness, hallucinations, delusions, hypertension, nausea, confusion, dizziness, vertigo and chest pain. Acute kidney injury has also been strongly associated with SCB use. Treatment mostly involves symptom management and supportive care. More research is needed to identify which contaminants are typically found in synthetic marijuana and to understand the interactions between different SBCs to better predict adverse health outcomes.

  18. Non-Invasive Spectral Phenotyping Methods can Improve and Accelerate Cercospora Disease Scoring in Sugar Beet Breeding

    Directory of Open Access Journals (Sweden)

    Marcus Jansen

    2014-05-01

    Full Text Available Breeding for Cercospora resistant sugar beet cultivars requires field experiments for testing resistance levels of candidate genotypes in conditions that are close to agricultural cultivation. Non-invasive spectral phenotyping methods can support and accelerate resistance rating and thereby speed up breeding process. In a case study, experimental field plots with strongly infected beet genotypes of different resistance levels were measured with two different spectrometers. Vegetation indices were calculated from measured wavelength signature to determine leaf physiological status, e.g., greenness with the Normalized Differenced Vegetation Index (NDVI, leaf water content with the Leaf Water Index (LWI and Cercospora disease severity with the Cercospora Leaf Spot Index (CLSI. Indices values correlated significantly with visually scored disease severity, thus connecting the classical breeders’ scoring approach with advanced non-invasive technology.

  19. Acceleration of Gas Flow Simulations in Dual-Continuum Porous Media Based on the Mass-Conservation POD Method

    KAUST Repository

    Wang, Yi

    2017-09-12

    Reduced-order modeling approaches for gas flow in dual-porosity dual-permeability porous media are studied based on the proper orthogonal decomposition (POD) method combined with Galerkin projection. The typical modeling approach for non-porous-medium liquid flow problems is not appropriate for this compressible gas flow in a dual-continuum porous media. The reason is that non-zero mass transfer for the dual-continuum system can be generated artificially via the typical POD projection, violating the mass-conservation nature and causing the failure of the POD modeling. A new POD modeling approach is proposed considering the mass conservation of the whole matrix fracture system. Computation can be accelerated as much as 720 times with high precision (reconstruction errors as slow as 7.69 × 10−4%~3.87% for the matrix and 8.27 × 10−4%~2.84% for the fracture).

  20. Method for 236U Determination in Seawater Using Flow Injection Extraction Chromatography and Accelerator Mass Spectrometry

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Steier, Peter

    2015-01-01

    An automated analytical method implemented in a flow injection (FI) system was developed for rapid determination of 236U in 10 L seawater samples. 238U was used as a chemical yield tracer for the whole procedure, in which extraction chromatography (UTEVA) was exploited to purify uranium, after...... experimental parameters affecting the analytical effectiveness were investigated and optimized in order to achieve high chemical yields and simple and rapid analysis as well as low procedure background. Besides, the operational conditions for the target preparation prior to the AMS measurement were optimized......, on the basis of studying the coprecipitation behavior of uranium with iron hydroxide. The analytical results indicate that the developed method is simple and robust, providing satisfactory chemical yields (80−100%) and high analysis speed (4 h/sample), which could be an appealing alternative to conventional...

  1. Dental movement acceleration: Literature review by an alternative scientific evidence method

    OpenAIRE

    Camacho, Angela Domínguez; Cujar, Sergio Andres Velásquez

    2014-01-01

    The aim of this study was to analyze the majority of publications using effective methods to speed up orthodontic treatment and determine which publications carry high evidence-based value. The literature published in Pubmed from 1984 to 2013 was reviewed, in addition to well-known reports that were not classified under this database. To facilitate evidence-based decision making, guidelines such as the Consolidation Standards of Reporting Trials, Preferred Reporting items for systematic Revie...

  2. Efficient combination of acceleration techniques applied to high frequency methods for solving radiation and scattering problems

    Science.gov (United States)

    Lozano, Lorena; Algar, Ma Jesús; García, Eliseo; González, Iván; Cátedra, Felipe

    2017-12-01

    An improved ray-tracing method applied to high-frequency techniques such as the Uniform Theory of Diffraction (UTD) is presented. The main goal is to increase the speed of the analysis of complex structures while considering a vast number of observation directions and taking into account multiple bounces. The method is based on a combination of the Angular Z-Buffer (AZB), the Space Volumetric Partitioning (SVP) algorithm and the A∗ heuristic search method to treat multiple bounces. In addition, a Master Point strategy was developed to analyze efficiently a large number of Near-Field points or Far-Field directions. This technique can be applied to electromagnetic radiation problems, scattering analysis, propagation at urban or indoor environments and to the mutual coupling between antennas. Due to its efficiency, its application is suitable to study large antennas radiation patterns and even its interactions with complex environments, including satellites, ships, aircrafts, cities or another complex electrically large bodies. The new technique appears to be extremely efficient at these applications even when considering multiple bounces.

  3. Convergence acceleration of Navier-Stokes equation using adaptive wavelet method

    International Nuclear Information System (INIS)

    Kang, Hyung Min; Ghafoor, Imran; Lee, Do Hyung

    2010-01-01

    An efficient adaptive wavelet method is proposed for the enhancement of computational efficiency of the Navier-Stokes equations. The method is based on sparse point representation (SPR), which uses the wavelet decomposition and thresholding to obtain a sparsely distributed dataset. The threshold mechanism is modified in order to maintain the spatial accuracy of a conventional Navier-Stokes solver by adapting the threshold value to the order of spatial truncation error. The computational grid can be dynamically adapted to a transient solution to reflect local changes in the solution. The flux evaluation is then carried out only at the points of the adapted dataset, which reduces the computational effort and memory requirements. A stabilization technique is also implemented to avoid the additional numerical errors introduced by the threshold procedure. The numerical results of the adaptive wavelet method are compared with a conventional solver to validate the enhancement in computational efficiency of Navier-Stokes equations without the degeneration of the numerical accuracy of a conventional solver

  4. GPUs, a New Tool of Acceleration in CFD: Efficiency and Reliability on Smoothed Particle Hydrodynamics Methods

    Science.gov (United States)

    Crespo, Alejandro C.; Dominguez, Jose M.; Barreiro, Anxo; Gómez-Gesteira, Moncho; Rogers, Benedict D.

    2011-01-01

    Smoothed Particle Hydrodynamics (SPH) is a numerical method commonly used in Computational Fluid Dynamics (CFD) to simulate complex free-surface flows. Simulations with this mesh-free particle method far exceed the capacity of a single processor. In this paper, as part of a dual-functioning code for either central processing units (CPUs) or Graphics Processor Units (GPUs), a parallelisation using GPUs is presented. The GPU parallelisation technique uses the Compute Unified Device Architecture (CUDA) of nVidia devices. Simulations with more than one million particles on a single GPU card exhibit speedups of up to two orders of magnitude over using a single-core CPU. It is demonstrated that the code achieves different speedups with different CUDA-enabled GPUs. The numerical behaviour of the SPH code is validated with a standard benchmark test case of dam break flow impacting on an obstacle where good agreement with the experimental results is observed. Both the achieved speed-ups and the quantitative agreement with experiments suggest that CUDA-based GPU programming can be used in SPH methods with efficiency and reliability. PMID:21695185

  5. A method to accelerate creation of plasma etch recipes using physics and Bayesian statistics

    Science.gov (United States)

    Chopra, Meghali J.; Verma, Rahul; Lane, Austin; Willson, C. G.; Bonnecaze, Roger T.

    2017-03-01

    Next generation semiconductor technologies like high density memory storage require precise 2D and 3D nanopatterns. Plasma etching processes are essential to achieving the nanoscale precision required for these structures. Current plasma process development methods rely primarily on iterative trial and error or factorial design of experiment (DOE) to define the plasma process space. Here we evaluate the efficacy of the software tool Recipe Optimization for Deposition and Etching (RODEo) against standard industry methods at determining the process parameters of a high density O2 plasma system with three case studies. In the first case study, we demonstrate that RODEo is able to predict etch rates more accurately than a regression model based on a full factorial design while using 40% fewer experiments. In the second case study, we demonstrate that RODEo performs significantly better than a full factorial DOE at identifying optimal process conditions to maximize anisotropy. In the third case study we experimentally show how RODEo maximizes etch rates while using half the experiments of a full factorial DOE method. With enhanced process predictions and more accurate maps of the process space, RODEo reduces the number of experiments required to develop and optimize plasma processes.

  6. Accelerating finite-rate chemical kinetics with coprocessors: Comparing vectorization methods on GPUs, MICs, and CPUs

    Science.gov (United States)

    Stone, Christopher P.; Alferman, Andrew T.; Niemeyer, Kyle E.

    2018-05-01

    Accurate and efficient methods for solving stiff ordinary differential equations (ODEs) are a critical component of turbulent combustion simulations with finite-rate chemistry. The ODEs governing the chemical kinetics at each mesh point are decoupled by operator-splitting allowing each to be solved concurrently. An efficient ODE solver must then take into account the available thread and instruction-level parallelism of the underlying hardware, especially on many-core coprocessors, as well as the numerical efficiency. A stiff Rosenbrock and a nonstiff Runge-Kutta ODE solver are both implemented using the single instruction, multiple thread (SIMT) and single instruction, multiple data (SIMD) paradigms within OpenCL. Both methods solve multiple ODEs concurrently within the same instruction stream. The performance of these parallel implementations was measured on three chemical kinetic models of increasing size across several multicore and many-core platforms. Two separate benchmarks were conducted to clearly determine any performance advantage offered by either method. The first benchmark measured the run-time of evaluating the right-hand-side source terms in parallel and the second benchmark integrated a series of constant-pressure, homogeneous reactors using the Rosenbrock and Runge-Kutta solvers. The right-hand-side evaluations with SIMD parallelism on the host multicore Xeon CPU and many-core Xeon Phi co-processor performed approximately three times faster than the baseline multithreaded C++ code. The SIMT parallel model on the host and Phi was 13%-35% slower than the baseline while the SIMT model on the NVIDIA Kepler GPU provided approximately the same performance as the SIMD model on the Phi. The runtimes for both ODE solvers decreased significantly with the SIMD implementations on the host CPU (2.5-2.7 ×) and Xeon Phi coprocessor (4.7-4.9 ×) compared to the baseline parallel code. The SIMT implementations on the GPU ran 1.5-1.6 times faster than the baseline

  7. Shelf Life Estimation of Instant Noodle From Sago Starch and Catfish (Pangasius SP.) Using Accelerated Method

    OpenAIRE

    Siregar, Harapan

    2014-01-01

    The research purpose was to estimate the shelf life of noodle from sagostarch and catfish (Pangasius sp.). Shelf life is one of the requirements that mustbe met before marketing of food products. Shelf life estimation was using theaccelerated method of observation of instant noodles for 28 days at three differenttemperatures namely 35°C, 45°C and 55°C. Parameters observed during thestorage process were the assessment of sensory level of rancidity and TBA value.Results show that shelf life of ...

  8. Contrast source inversion (CSI) method to cross-hole radio-imaging (RIM) data - Part 2: A complex synthetic example and a case study

    Science.gov (United States)

    Li, Yongxing; Smith, Richard S.

    2018-03-01

    We present two examples of using the contrast source inversion (CSI) method to invert synthetic radio-imaging (RIM) data and field data. The synthetic model has two isolated conductors (one perfect conductor and one moderate conductor) embedded in a layered background. After inversion, we can identify the two conductors on the inverted image. The shape of the perfect conductor is better resolved than the shape of the moderate conductor. The inverted conductivity values of the two conductors are approximately the same, which demonstrates that the conductivity values cannot be correctly interpreted from the CSI results. The boundaries and the tilts of the upper and the lower conductive layers on the background can also be inferred from the results, but the centre parts of conductive layers in the inversion results are more conductive than the parts close to the boreholes. We used the straight-ray tomographic imaging method and the CSI method to invert the RIM field data collected using the FARA system between two boreholes in a mining area in Sudbury, Canada. The RIM data include the amplitude and the phase data collected using three frequencies: 312.5 kHz, 625 kHz and 1250 kHz. The data close to the ground surface have high amplitude values and complicated phase fluctuations, which are inferred to be contaminated by the reflected or refracted electromagnetic (EM) fields from the ground surface, and are removed for all frequencies. Higher-frequency EM waves attenuate more quickly in the subsurface environment, and the locations where the measurements are dominated by noise are also removed. When the data are interpreted with the straight-ray method, the images differ substantially for different frequencies. In addition, there are some unexpected features in the images, which are difficult to interpret. Compared with the straight-ray imaging results, the inversion results with the CSI method are more consistent for different frequencies. On the basis of what we learnt

  9. Synthetic biology and occupational risk.

    Science.gov (United States)

    Howard, John; Murashov, Vladimir; Schulte, Paul

    2017-03-01

    Synthetic biology is an emerging interdisciplinary field of biotechnology that involves applying the principles of engineering and chemical design to biological systems. Biosafety professionals have done an excellent job in addressing research laboratory safety as synthetic biology and gene editing have emerged from the larger field of biotechnology. Despite these efforts, risks posed by synthetic biology are of increasing concern as research procedures scale up to industrial processes in the larger bioeconomy. A greater number and variety of workers will be exposed to commercial synthetic biology risks in the future, including risks to a variety of workers from the use of lentiviral vectors as gene transfer devices. There is a need to review and enhance current protection measures in the field of synthetic biology, whether in experimental laboratories where new advances are being researched, in health care settings where treatments using viral vectors as gene delivery systems are increasingly being used, or in the industrial bioeconomy. Enhanced worker protection measures should include increased injury and illness surveillance of the synthetic biology workforce; proactive risk assessment and management of synthetic biology products; research on the relative effectiveness of extrinsic and intrinsic biocontainment methods; specific safety guidance for synthetic biology industrial processes; determination of appropriate medical mitigation measures for lentiviral vector exposure incidents; and greater awareness and involvement in synthetic biology safety by the general occupational safety and health community as well as by government occupational safety and health research and regulatory agencies.

  10. Papaya Tree Detection with UAV Images Using a GPU-Accelerated Scale-Space Filtering Method

    Directory of Open Access Journals (Sweden)

    Hao Jiang

    2017-07-01

    Full Text Available The use of unmanned aerial vehicles (UAV can allow individual tree detection for forest inventories in a cost-effective way. The scale-space filtering (SSF algorithm is commonly used and has the capability of detecting trees of different crown sizes. In this study, we made two improvements with regard to the existing method and implementations. First, we incorporated SSF with a Lab color transformation to reduce over-detection problems associated with the original luminance image. Second, we ported four of the most time-consuming processes to the graphics processing unit (GPU to improve computational efficiency. The proposed method was implemented using PyCUDA, which enabled access to NVIDIA’s compute unified device architecture (CUDA through high-level scripting of the Python language. Our experiments were conducted using two images captured by the DJI Phantom 3 Professional and a most recent NVIDIA GPU GTX1080. The resulting accuracy was high, with an F-measure larger than 0.94. The speedup achieved by our parallel implementation was 44.77 and 28.54 for the first and second test image, respectively. For each 4000 × 3000 image, the total runtime was less than 1 s, which was sufficient for real-time performance and interactive application.

  11. Powered by DFT: Screening methods that accelerate materials development for hydrogen in metals applications.

    Science.gov (United States)

    Nicholson, Kelly M; Chandrasekhar, Nita; Sholl, David S

    2014-11-18

    CONSPECTUS: Not only is hydrogen critical for current chemical and refining processes, it is also projected to be an important energy carrier for future green energy systems such as fuel cell vehicles. Scientists have examined light metal hydrides for this purpose, which need to have both good thermodynamic properties and fast charging/discharging kinetics. The properties of hydrogen in metals are also important in the development of membranes for hydrogen purification. In this Account, we highlight our recent work aimed at the large scale screening of metal-based systems with either favorable hydrogen capacities and thermodynamics for hydrogen storage in metal hydrides for use in onboard fuel cell vehicles or promising hydrogen permeabilities relative to pure Pd for hydrogen separation from high temperature mixed gas streams using dense metal membranes. Previously, chemists have found that the metal hydrides need to hit a stability sweet spot: if the compound is too stable, it will not release enough hydrogen under low temperatures; if the compound is too unstable, the reaction may not be reversible under practical conditions. Fortunately, we can use DFT-based methods to assess this stability via prediction of thermodynamic properties, equilibrium reaction pathways, and phase diagrams for candidate metal hydride systems with reasonable accuracy using only proposed crystal structures and compositions as inputs. We have efficiently screened millions of mixtures of pure metals, metal hydrides, and alloys to identify promising reaction schemes via the grand canonical linear programming method. Pure Pd and Pd-based membranes have ideal hydrogen selectivities over other gases but suffer shortcomings such as sensitivity to sulfur poisoning and hydrogen embrittlement. Using a combination of detailed DFT, Monte Carlo techniques, and simplified models, we are able to accurately predict hydrogen permeabilities of metal membranes and screen large libraries of candidate alloys

  12. A Precision-Positioning Method for a High-Acceleration Low-Load Mechanism Based on Optimal Spatial and Temporal Distribution of Inertial Energy

    Directory of Open Access Journals (Sweden)

    Xin Chen

    2015-09-01

    Full Text Available High-speed and precision positioning are fundamental requirements for high-acceleration low-load mechanisms in integrated circuit (IC packaging equipment. In this paper, we derive the transient nonlinear dynamicresponse equations of high-acceleration mechanisms, which reveal that stiffness, frequency, damping, and driving frequency are the primary factors. Therefore, we propose a new structural optimization and velocity-planning method for the precision positioning of a high-acceleration mechanism based on optimal spatial and temporal distribution of inertial energy. For structural optimization, we first reviewed the commonly flexible multibody dynamic optimization using equivalent static loads method (ESLM, and then we selected the modified ESLM for optimal spatial distribution of inertial energy; hence, not only the stiffness but also the inertia and frequency of the real modal shapes are considered. For velocity planning, we developed a new velocity-planning method based on nonlinear dynamic-response optimization with varying motion conditions. Our method was verified on a high-acceleration die bonder. The amplitude of residual vibration could be decreased by more than 20% via structural optimization and the positioning time could be reduced by more than 40% via asymmetric variable velocity planning. This method provides an effective theoretical support for the precision positioning of high-acceleration low-load mechanisms.

  13. Investigation of using shrinking method in construction of Institute for Research in Fundamental Sciences Electron Linear Accelerator TW-tube (IPM TW-Linac tube)

    International Nuclear Information System (INIS)

    Ghasemi, F.; Davani, F. Abbasi

    2015-01-01

    Due to Iran's growing need for accelerators in various applications, IPM's electron Linac project has been defined. This accelerator is a 15 MeV energy S-band traveling-wave accelerator which is being designed and constructed based on the klystron that has been built in Iran. Based on the design, operating mode is π /2 and the accelerating chamber consists of two 60cm long tubes with constant impedance and a 30cm long buncher. Amongst all construction methods, shrinking method is selected for construction of IPM's electron Linac tube because it has a simple procedure and there is no need for large vacuum or hydrogen furnaces. In this paper, different aspects of this method are investigated. According to the calculations, linear ratio of frequency alteration to radius change is 787.8 MHz/cm, and the maximum deformation at the tube wall where disks and the tube make contact is 2.7μ m. Applying shrinking method for construction of 8- and 24-cavity tubes results in satisfactory frequency and quality factor. Average deviations of cavities frequency of 8- and 24-cavity tubes to the design values are 0.68 MHz and 1.8 MHz respectively before tune and 0.2 MHz and 0.4 MHz after tune. Accelerating tubes, buncher, and high power couplers of IPM's electron linac are constructed using shrinking method

  14. Accelerator based nuclear analytical methods for trace element studies in materials- calcified tissues

    International Nuclear Information System (INIS)

    Chaudhri, M. Anwar

    2006-01-01

    Full text: Various nuclear analytical methods have been developed and applied to determine the elemental composition of calcified tissues (teeth and bones). Fluorine was determined by prompt gamma activation analysis through the 19 F(p,αγ) 16 O reaction. Carbon was measured by activation analysis with He-3 ions, and the technique of Proton-Induced X-ray Emission (PIXE) was applied to simultaneously determine Ca, P, and trace elements in well-documented teeth. Dental hard tissues: enamel, dentine, cementum, and their junctions, as well as different parts of the same tissue, were examined separately. Furthermore, using a Proton Microprobe, we measured the surface distribution of F and other elements on and around carious lesions on the enamel. The depth profiles of F, and other elements, were also measured right up to the amelodentin junction. (author)

  15. GPU-accelerated Direct Sampling method for multiple-point statistical simulation

    Science.gov (United States)

    Huang, Tao; Li, Xue; Zhang, Ting; Lu, De-Tang

    2013-08-01

    Geostatistical simulation techniques have become a widely used tool for the modeling of oil and gas reservoirs and the assessment of uncertainty. The Direct Sampling (DS) algorithm is a recent multiple-point statistical simulation technique. It directly samples the training image (TI) during the simulation process by calculating distances between the TI patterns and the given data events found in the simulation grid (SG). Omitting the prior storage of all the TI patterns in a database, the DS algorithm can be used to simulate categorical, continuous and multivariate variables. Three fundamental input parameters are required for the definition of DS applications: the number of neighbors n, the acceptance threshold t and the fraction of the TI to scan f. For very large grids and complex spatial models with more severe parameter restrictions, the computational costs in terms of simulation time often become the bottleneck of practical applications. This paper focuses on an innovative implementation of the Direct Sampling method which exploits the benefits of graphics processing units (GPUs) to improve computational performance. Parallel schemes are applied to deal with two of the DS input parameters, n and f. Performance tests are carried out with large 3D grid size and the results are compared with those obtained based on the simulations with central processing units (CPU). The comparison indicates that the use of GPUs reduces the computation time by a factor of 10X-100X depending on the input parameters. Moreover, the concept of the search ellipsoid can be conveniently combined with the flexible data template of the DS method, and our experimental results of sand channels reconstruction show that it can improve the reproduction of the long-range connectivity patterns.

  16. Synthetic Botany.

    Science.gov (United States)

    Boehm, Christian R; Pollak, Bernardo; Purswani, Nuri; Patron, Nicola; Haseloff, Jim

    2017-07-05

    Plants are attractive platforms for synthetic biology and metabolic engineering. Plants' modular and plastic body plans, capacity for photosynthesis, extensive secondary metabolism, and agronomic systems for large-scale production make them ideal targets for genetic reprogramming. However, efforts in this area have been constrained by slow growth, long life cycles, the requirement for specialized facilities, a paucity of efficient tools for genetic manipulation, and the complexity of multicellularity. There is a need for better experimental and theoretical frameworks to understand the way genetic networks, cellular populations, and tissue-wide physical processes interact at different scales. We highlight new approaches to the DNA-based manipulation of plants and the use of advanced quantitative imaging techniques in simple plant models such as Marchantia polymorpha. These offer the prospects of improved understanding of plant dynamics and new approaches to rational engineering of plant traits. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  17. Synthetic Brainbows

    KAUST Repository

    Wan, Y.

    2013-06-01

    Brainbow is a genetic engineering technique that randomly colorizes cells. Biological samples processed with this technique and imaged with confocal microscopy have distinctive colors for individual cells. Complex cellular structures can then be easily visualized. However, the complexity of the Brainbow technique limits its applications. In practice, most confocal microscopy scans use different florescence staining with typically at most three distinct cellular structures. These structures are often packed and obscure each other in rendered images making analysis difficult. In this paper, we leverage a process known as GPU framebuffer feedback loops to synthesize Brainbow-like images. In addition, we incorporate ID shuffing and Monte-Carlo sampling into our technique, so that it can be applied to single-channel confocal microscopy data. The synthesized Brainbow images are presented to domain experts with positive feedback. A user survey demonstrates that our synthetic Brainbow technique improves visualizations of volume data with complex structures for biologists.

  18. Microfluidic Technologies for Synthetic Biology

    Directory of Open Access Journals (Sweden)

    Sung Kuk Lee

    2011-06-01

    Full Text Available Microfluidic technologies have shown powerful abilities for reducing cost, time, and labor, and at the same time, for increasing accuracy, throughput, and performance in the analysis of biological and biochemical samples compared with the conventional, macroscale instruments. Synthetic biology is an emerging field of biology and has drawn much attraction due to its potential to create novel, functional biological parts and systems for special purposes. Since it is believed that the development of synthetic biology can be accelerated through the use of microfluidic technology, in this review work we focus our discussion on the latest microfluidic technologies that can provide unprecedented means in synthetic biology for dynamic profiling of gene expression/regulation with high resolution, highly sensitive on-chip and off-chip detection of metabolites, and whole-cell analysis.

  19. SNaPe: a versatile method to generate multiplexed protein fusions using synthetic linker peptides for in vitro applications.

    Science.gov (United States)

    Ulrich, Veronika; Cryle, Max J

    2017-01-01

    Understanding the structure and function of protein complexes and multi-domain proteins is highly important in biology, although the in vitro characterization of these systems is often complicated by their size or the transient nature of protein/protein interactions. To assist in the characterization of such protein complexes, we have developed a modular approach to fusion protein generation that relies upon Sortase-mediated and Native chemical ligation using synthetic Peptide linkers (SNaPe) to link two separately expressed proteins. In this approach, we utilize two separate linking steps - sortase-mediated and native chemical ligation - together with a library of peptide linkers to generate libraries of fusion proteins. We have demonstrated the viability of SNaPe to generate libraries from fusion protein constructs taken from the biosynthetic enzymes responsible for late stage aglycone assembly during glycopeptide antibiotic biosynthesis. Crucially, SNaPe was able to generate fusion proteins that are inaccessible via direct expression of the fusion construct itself. This highlights the advantages of SNaPe to not only access fusion proteins that have been previously unavailable for biochemical and structural characterization but also to do so in a manner that enables the linker itself to be controlled as an experimental parameter of fusion protein generation. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

  20. Improved performance of mesoscopic perovskite solar cell using an accelerated crystalline formation method

    Science.gov (United States)

    Sidhik, Siraj; Esparza, Diego; Martínez-Benítez, Alejandro; López-Luke, Tzarara; Carriles, Ramón; De la Rosa, Elder

    2017-10-01

    Highly smooth organo-lead halide perovskite (OHP) films with less intra-granular defects are necessary to minimize the non-radiative carrier recombination in photovoltaic devices. Herein, a simple air-extraction anti-solvent deposition (AAD) technique is proposed to improve the quality of perovskite films. An air extraction process accompanied by anti-solvent washing helps to improve the morphology of perovskite, leading to smooth, homogeneous, compact, pin-hole free and densely packed films. Perovskite films with an average roughness of 5.01 nm, which is the smoothest morphology in mesoscopic-perovskite solar cell to the extent of our knowledge, high crystallinity, and a crystallite size in the range of ∼500 nm to 1 μm have been achieved. Average power conversion efficiency (PCE) of 16.99% for 15 cells and a best PCE of 17.70% with a high open circuit voltage of 1.075 and fill factor of 74.22% were achieved using the AAD approach without a glove box. The cells exhibit virtually no hysteresis. These efficiency values are approximately 37.68% higher than the cells fabricated using anti-solvent process without air-extraction, where an average efficiency of 12.34% was measured. This method demonstrates high reproducibility and can be employed for the large scale production of PSC at reduced cost.

  1. Validation of the SCEC broadband platform V14.3 simulation methods using pseudo spectral acceleration data

    Science.gov (United States)

    Dreger, Douglas S.; Beroza, Gregory C.; Day, Steven M.; Goulet, Christine A.; Jordan, Thomas H; Spudich, Paul A.; Stewart, Jonathan P.

    2015-01-01

    This paper summarizes the evaluation of ground motion simulation methods implemented on the SCEC Broadband Platform (BBP), version 14.3 (as of March 2014). A seven-member panel, the authorship of this article, was formed to evaluate those methods for the prediction of pseudo-­‐spectral accelerations (PSAs) of ground motion. The panel’s mandate was to evaluate the methods using tools developed through the validation exercise (Goulet et al. ,2014), and to define validation metrics for the assessment of the methods’ performance. This paper summarizes the evaluation process and conclusions from the panel. The five broadband, finite-source simulation methods on the BBP include two deterministic approaches herein referred to as CSM (Anderson, 2014) and UCSB (Crempien and Archuleta, 2014); a band-­‐limited stochastic white noise method called EXSIM (Atkinson and Assatourians, 2014); and two hybrid approaches, referred to as G&P (Graves and Pitarka, 2014) and SDSU (Olsen and Takedatsu, 2014), which utilize a deterministic Green’s function approach for periods longer than 1 second and stochastic methods for periods shorter than 1 second. Two acceptance tests were defined to validate the broadband finite‐source ground methods (Goulet et al., 2014). Part A compared observed and simulated PSAs for periods from 0.01 to 10 seconds for 12 moderate to large earthquakes located in California, Japan, and the eastern US. Part B compared the median simulated PSAs to published NGA-­‐West1 (Abrahamson and Silva, 2008; Boore and Atkinson, 2008; Campbell and Bozorgnia, 2008; and Chiou and Youngs, 2008) ground motion prediction equations (GMPEs) for specific magnitude and distance cases using a pass-­‐fail criteria based on a defined acceptable range around the spectral shape of the GMPEs. For the initial Part A and Part B validation exercises during the summer of 2013, the software for the five methods was locked in at version 13.6 (see Maechling et al., 2014). In the

  2. Acceleration Mechanisms

    OpenAIRE

    Melrose, D. B.

    2009-01-01

    Glossary I. Background and context of the subject II. Stochastic acceleration III. Resonant scattering IV. Diffusive shock acceleration V. DSA at multiple shocks VI. Applications of DSA VII. Acceleration by parallel electric fields VIII. Other acceleration mechanisms IX. Future directions X. Appendix: Quasilinear equations XI. Bibliography

  3. Generating realistic synthetic meteoroid orbits

    Science.gov (United States)

    Vida, Denis; Brown, Peter G.; Campbell-Brown, Margaret

    2017-11-01

    Context. Generating a synthetic dataset of meteoroid orbits is a crucial step in analysing the probabilities of random grouping of meteoroid orbits in automated meteor shower surveys. Recent works have shown the importance of choosing a low similarity threshold value of meteoroid orbits, some pointing out that the recent meteor shower surveys produced false positives due to similarity thresholds which were too high. On the other hand, the methods of synthetic meteoroid orbit generation introduce additional biases into the data, thus making the final decision on an appropriate threshold value uncertain. Aims. As a part of the ongoing effort to determine the nature of meteor showers and improve automated methods, it was decided to tackle the problem of synthetic meteoroid orbit generation, the main goal being to reproduce the underlying structure and the statistics of the observed data in the synthetic orbits. Methods. A new method of generating synthetic meteoroid orbits using the Kernel Density Estimation method is presented. Several types of approaches are recommended, depending on whether one strives to preserve the data structure, the data statistics or to have a compromise between the two. Results. The improvements over the existing methods of synthetic orbit generation are demonstrated. The comparison between the previous and newly developed methods are given, as well as the visualization tools one can use to estimate the influence of different input parameters on the final data.

  4. An accelerated method for the detection of Extended-Spectrum B- Lactamases in urinary isolates of Escherichia Coli and Klebsiella pneumoniae

    International Nuclear Information System (INIS)

    Kader, Abdulrahman A.; Kumar, A.; Krishna, A.; Zaman, M.N.

    2006-01-01

    We prospectively studied an accelerated phenotypic method by incorporating the double disk synergy test in the standard Kirby-Bauer disk diffusion susceptibility testing, to evaluate a protocol for the rapid detection of extended of extended-spectrum B-lactamases (ESBL) in urinary isolates of Escherichia coli (E. coli) and Klebsiella, pneumoniae (K. pneumoniae). All ESBL-positive isolates were confirmed by the standard Clinical Laboratory Standards Institute (CLSI) confirmatory disk diffusion method. Between November 2004 and December 2005, a total of 6988 urine specimens were analyzed of which 776 (11%) showed significant growth. They included E. coli in 577 cases (74%) and K. pneumoniae in 199 (25.6%). Of these, 63 E. coli (8%) and 15 K. pneumoniae (7.5%) were positive for ESBL by the accelerated and CLSI methods. Compared to the standard CLSI method, the accelerated method reduced the ESBL detection time from two days to one day. We conclude that the accelerated ESBL detection technique used by us in this study is a reliable and rapid method for detecting ESBL in urinary isolates of E. coli and K. pneumoniae. (author)

  5. Development of new peptide synthetic method of enzyme using the extraction reactivity; Chushutsu hanno wo mochiita shiki pepuchido koso goseiho no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Makoto [Oita University, Oita (Japan)

    1999-03-05

    Recently, taste and bioactivation of large number of oligopeptide become clear, and the development of the efficient synthetic method becomes the urgency. In the production process by conventional enzyme reaction which combined the crystallization, because the solubility of the product to the water which is reaction solvent is low, the yield remained at about 60%, and the problem of reaction inhibition of the product by the crystal had also been indicated. In the enzyme synthesis of the aspartame in which he is the representative oligopeptide, it aimed at the establishment of the new synthesis method which can improve yield and reaction rate, while the segregation enzyme was continuously utilized. In this synthetic method, supply of organic solvent which dissolved the substrate, extraction of the substrate from organic solvent to water phase, synthesis reaction by the segregation enzyme in water phase, extraction of the aspartame which is a product from water phase to organic solvent progress, and they continuously progress by one complete mixing reactor. The process which controlled these speeds and yields was quantitatively analyzed, and material balance style considering substrate, enzyme and mass transfer of the product and enzyme reaction speed was deduced. The optimum operating condition for improving yield and productivity of the purpose product using this solution was examined, and optimum supply concentration and agitation speed of aspartic acid which was a substrate were started, and the optimum operating condition which realizes the improvement in high yield and productivity over 90% of the aspartame was clarified. Like this, it is that this research adopts features of liquid Citrus nobilis two-phase partition for the enzyme synthesis of the aspartame, and it is considered that there is a value, because it is the creative research which verified that the productivity can be greatly improved by the utilization of the chemical-engineering technique, and

  6. Synthetic LDL as targeted drug delivery vehicle

    Science.gov (United States)

    Forte, Trudy M [Berkeley, CA; Nikanjam, Mina [Richmond, CA

    2012-08-28

    The present invention provides a synthetic LDL nanoparticle comprising a lipid moiety and a synthetic chimeric peptide so as to be capable of binding the LDL receptor. The synthetic LDL nanoparticle of the present invention is capable of incorporating and targeting therapeutics to cells expressing the LDL receptor for diseases associated with the expression of the LDL receptor such as central nervous system diseases. The invention further provides methods of using such synthetic LDL nanoparticles.

  7. Manufacturing and characterization of ceramic pigment Zn1-xFexCr2O4 by synthetic non conventional methods

    International Nuclear Information System (INIS)

    Nieves, Leidy Johana Jaramillo; Baena, Oscar Jaime Restrepo

    2012-01-01

    The ceramic pigment with structure Zn 1-x Fe x Cr 2 O 4 (x = 0, 0.5, 1) was synthesized by non conventional methods of coprecipitation assisted by ultrasound and milling of high energy. This pigment was characterized by XRD, XRF, SEM, UV-VIS spectrophotometry and CIELab colorimetry. The aim of this work was studied two alternative methods to the traditional method of synthesis, evaluating the pigment properties, varying the stoichiometry, such as structure, composition, morphology and colorimetric coordinates. The results showed that is possible to obtain the desired crystalline structure at temperatures below 1000 ° C in both cases, also expected hues are obtained according to each stoichiometry, which shows the advantages of using methods non conventional when produce these pigments, since it has a higher controlling the composition, stoichiometry and is obtained at temperatures below compared with traditional ceramic method

  8. High-throughput GC-ECD analysis of PCBs in food by accelerated solvent extraction. Method validation

    Energy Technology Data Exchange (ETDEWEB)

    Piersanti, A.; Fioroni, L.; Paoloni, A.; Tavoloni, T.; Pecorelli, I.; Galarini, R. [Istituto Zooprofilattico Sperimentale dell' Umbria e delle Marche, Perugia (Italy)

    2004-09-15

    In the year 2000 the determination of the PCBs in food commodities was introduced in the Italian national residue control plan in which government labs were requested to estimate the total PCB content as sum of seven more representative congeners. Later on, in 2001, it was decided that a more appropriate estimation of the total PCBs was possible through analysis of eighteen rather than seven congeners. Therefore the need for simple and validated analytical methods arose. In this work a method for the analysis of the PCBs 18-congeners (T{sub 3}CB-28, T{sub 4}CB-52, P{sub 5}CB-95, P{sub 5}CB-99, P{sub 5}CB-101, P{sub 5}CB-105, P{sub 5}CB-110, P{sub 5}CB-118, H{sub 6}CB-138, H{sub 6}CB-146, H{sub 6}CB-149, H{sub 6}CB-151, H{sub 6}CB-153, H{sub 7}CB-170, H{sub 7}CB-177, H{sub 7}CB-180, H{sub 7}CB-183, H{sub 7}CB-187) is reported. This has been set up taking in account the advantages of the automated and high efficient Accelerated Solvent Extraction together with good purification achieved by a one-step acidic-extrelut/silica chromatography. The instrumental analysis is performed by capillary-GC equipped with an ECD detector. An in-house validation study has been made on swine muscle assessing the method performances in terms of limit of detection, response linearity range, trueness and precision.

  9. Optical synthetic aperture radar

    Science.gov (United States)

    Ilovitsh, Asaf; Zach, Shlomo; Zalevsky, Zeev

    2013-06-01

    A method is proposed for increasing the resolution of an object and overcoming the diffraction limit of an optical system installed on top of a moving imaging system, such as an airborne platform or satellite. The resolution improvement is obtained via a two-step process. First, three low resolution differently defocused images are captured and the optical phase is retrieved using an improved iterative Gershberg-Saxton based algorithm. The phase retrieval allows numerical back propagation of the field to the aperture plane. Second, the imaging system is shifted and the first step is repeated. The obtained optical fields at the aperture plane are combined and a synthetically increased lens aperture is generated along the direction of movement, yielding higher imaging resolution. The method resembles a well-known approach from the microwave regime called the synthetic aperture radar in which the antenna size is synthetically increased along the platform propagation direction. The proposed method is demonstrated via Matlab simulation as well as through laboratory experiment.

  10. Comparison of two synthetic methods to obtain [18F] N-(2-aminoethyl)-5-fluoropyridine-2-carboxamide, a potential MAO-B imaging tracer for PET

    International Nuclear Information System (INIS)

    Beer, H.-F.; Haeberli, M.; Ametamey, S.; Schubiger, P.A.

    1995-01-01

    The compound Ro 19-6327, N-(2-aminoethyl)-5-chloropyridine-2-carboxamide, is known to inhibit reversibly and site specifically the enzyme monoamine oxidase B (MAO-B). The 123 I-labelled iodo-analogue N-(2-aminoethyl)-5-iodopyridine-2-carboxamide (Ro 43-0463) was investigated successfully in human volunteers by means of SPET (Single Photon Emission Tomography). We developed therefore the synthesis and radiolabelling of the corresponding fluoro-analogue N-(2-aminoethyl)-5-fluoropyridine-2-carboxamide with 18 F in order to carry out PET (Positron Emission Tomography) investigations of MAO-B related neuropsychiatric diseases. For this purpose two synthetic approaches leading to the electrophilic and the nucleophilic methods of 18 F radiolabelling were undertaken. The nucleophilic approach appeared to be superior when factors such as precursor synthesis, beam time, specific activity and radiochemical purity of the product are considered. (author)

  11. Two Synthetic Methods for Preparation of Chiral Stationary Phases Using Crystalline Degradation Products of Vancomycin: Column Performance for Enantioseparation of Acidic and Basic Drugs.

    Science.gov (United States)

    Abdollahpour, Assem; Heydari, Rouhollah; Shamsipur, Mojtaba

    2017-07-01

    Two chiral stationary phases (CSPs) based on crystalline degradation products (CDPs) of vancomycin by using different synthetic methods were prepared and compared. Crystalline degradation products of vancomycin were produced by hydrolytic loss of ammonia from vancomycin molecules. Performances of two chiral columns prepared with these degradation products were investigated using several acidic and basic drugs as model analytes. Retention and resolution of these analytes on the prepared columns, as two main parameters, in enantioseparation were studied. The results demonstrated that the stationary phase preparation procedure has a significant effect on the column performance. The resolving powers of prepared columns for enantiomers resolution were changed with the variation in vancomycin-CDP coverage on the silica support. Elemental analysis was used to monitor the surface coverage of silica support by vancomycin-CDP. The results showed that both columns can be successfully applied to chiral separation studies.

  12. An Accelerated Test Method of Simultaneous Carbonation and Chloride Ion Ingress: Durability of Silica Fume Concrete in Severe Environments

    Directory of Open Access Journals (Sweden)

    S. A. Ghahari

    2016-01-01

    Full Text Available The effects of simultaneous carbonation and chloride ion attack on mechanical characteristics and durability of concrete containing silica fume have been investigated through an accelerated test method. Specimens containing different amounts of silica fume were maintained in an apparatus in which carbon dioxide pressure and concentration and relative humidity were kept constant, and wetting and drying cycles in saline water were applied. Surface resistivity, sorptivity, CO2 consumption, and carbonation and chloride ion ingress depths measurements were taken. Phase change due to carbonation and chloride ion attack was monitored by XRD analysis, and microstructures and interfacial transition zones were studied by implementing SEM as well as mercury intrusion porosimetry. It was expected to have a synergistic effect in the tidal zone where simultaneous carbonation and chloride ion attack happen. However, the observed reduced surface resistivity, compared to specimens maintained in CO2 gas, could be due to the moisture that is available near the surface, hindering CO2 from penetrating into the pores of the specimens. Moreover, the porosity analysis of the specimens showed that the sample containing silica fume cured in the tidal zone had 50.1% less total porosity than the plain cement paste cured in the same condition.

  13. Linearization of the Principal Component Analysis method for radiative transfer acceleration: Application to retrieval algorithms and sensitivity studies

    International Nuclear Information System (INIS)

    Spurr, R.; Natraj, V.; Lerot, C.; Van Roozendael, M.; Loyola, D.

    2013-01-01

    Principal Component Analysis (PCA) is a promising tool for enhancing radiative transfer (RT) performance. When applied to binned optical property data sets, PCA exploits redundancy in the optical data, and restricts the number of full multiple-scatter calculations to those optical states corresponding to the most important principal components, yet still maintaining high accuracy in the radiance approximations. We show that the entire PCA RT enhancement process is analytically differentiable with respect to any atmospheric or surface parameter, thus allowing for accurate and fast approximations of Jacobian matrices, in addition to radiances. This linearization greatly extends the power and scope of the PCA method to many remote sensing retrieval applications and sensitivity studies. In the first example, we examine accuracy for PCA-derived UV-backscatter radiance and Jacobian fields over a 290–340 nm window. In a second application, we show that performance for UV-based total ozone column retrieval is considerably improved without compromising the accuracy. -- Highlights: •Principal Component Analysis (PCA) of spectrally-binned atmospheric optical properties. •PCA-based accelerated radiative transfer with 2-stream model for fast multiple-scatter. •Atmospheric and surface property linearization of this PCA performance enhancement. •Accuracy of PCA enhancement for radiances and bulk-property Jacobians, 290–340 nm. •Application of PCA speed enhancement to UV backscatter total ozone retrievals

  14. Adapting capillary gel electrophoresis as a sensitive, high-throughput method to accelerate characterization of nucleic acid metabolic enzymes.

    Science.gov (United States)

    Greenough, Lucia; Schermerhorn, Kelly M; Mazzola, Laurie; Bybee, Joanna; Rivizzigno, Danielle; Cantin, Elizabeth; Slatko, Barton E; Gardner, Andrew F

    2016-01-29

    Detailed biochemical characterization of nucleic acid enzymes is fundamental to understanding nucleic acid metabolism, genome replication and repair. We report the development of a rapid, high-throughput fluorescence capillary gel electrophoresis method as an alternative to traditional polyacrylamide gel electrophoresis to characterize nucleic acid metabolic enzymes. The principles of assay design described here can be applied to nearly any enzyme system that acts on a fluorescently labeled oligonucleotide substrate. Herein, we describe several assays using this core capillary gel electrophoresis methodology to accelerate study of nucleic acid enzymes. First, assays were designed to examine DNA polymerase activities including nucleotide incorporation kinetics, strand displacement synthesis and 3'-5' exonuclease activity. Next, DNA repair activities of DNA ligase, flap endonuclease and RNase H2 were monitored. In addition, a multicolor assay that uses four different fluorescently labeled substrates in a single reaction was implemented to characterize GAN nuclease specificity. Finally, a dual-color fluorescence assay to monitor coupled enzyme reactions during Okazaki fragment maturation is described. These assays serve as a template to guide further technical development for enzyme characterization or nucleoside and non-nucleoside inhibitor screening in a high-throughput manner. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  15. Integer programming-based method for designing synthetic metabolic networks by Minimum Reaction Insertion in a Boolean model.

    Science.gov (United States)

    Lu, Wei; Tamura, Takeyuki; Song, Jiangning; Akutsu, Tatsuya

    2014-01-01

    In this paper, we consider the Minimum Reaction Insertion (MRI) problem for finding the minimum number of additional reactions from a reference metabolic network to a host metabolic network so that a target compound becomes producible in the revised host metabolic network in a Boolean model. Although a similar problem for larger networks is solvable in a flux balance analysis (FBA)-based model, the solution of the FBA-based model tends to include more reactions than that of the Boolean model. However, solving MRI using the Boolean model is computationally more expensive than using the FBA-based model since the Boolean model needs more integer variables. Therefore, in this study, to solve MRI for larger networks in the Boolean model, we have developed an efficient Integer Programming formalization method in which the number of integer variables is reduced by the notion of feedback vertex set and minimal valid assignment. As a result of computer experiments conducted using the data of metabolic networks of E. coli and reference networks downloaded from the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, we have found that the developed method can appropriately solve MRI in the Boolean model and is applicable to large scale-networks for which an exhaustive search does not work. We have also compared the developed method with the existing connectivity-based methods and FBA-based methods, and show the difference between the solutions of our method and the existing methods. A theoretical analysis of MRI is also conducted, and the NP-completeness of MRI is proved in the Boolean model. Our developed software is available at "http://sunflower.kuicr.kyoto-u.ac.jp/~rogi/minRect/minRect.html."

  16. Proposal for an alignment method of the CLIC linear accelerator - From geodesic networks to the active pre-alignment

    International Nuclear Information System (INIS)

    Touze, T.

    2011-01-01

    The compact linear collider (CLIC) is the particle accelerator project proposed by the european organization for nuclear research (CERN) for high energy physics after the large hadron collider (LHC). Because of the nano-metric scale of the CLIC leptons beams, the emittance growth budget is very tight. It induces alignment tolerances on the positions of the CLIC components that have never been achieved before. The last step of the CLIC alignment will be done according to the beam itself. It falls within the competence of the physicists. However, in order to implement the beam-based feedback, a challenging pre-alignment is required: 10 μm at 3σ along a 200 m sliding window. For such a precision, the proposed solution must be compatible with a feedback between the measurement and repositioning systems. The CLIC pre-alignment will have to be active. This thesis does not demonstrate the feasibility of the CLIC active pre-alignment but shows the way to the last developments that have to be done for that purpose. A method is proposed. Based on the management of the Helmert transformations between Euclidean coordinate systems, from the geodetic networks to the metrological measurements, this method is likely to solve the CLIC pre-alignment problem. Large scale facilities have been built and Monte-Carlo simulations have been made in order to validate the mathematical modeling of the measurement systems and of the alignment references. When this is done, it will be possible to extrapolate the modeling to the entire CLIC length. It will be the last step towards the demonstration of the CLIC pre-alignment feasibility. (author)

  17. Metabolomics tools for the synthetic biology of natural products.

    Science.gov (United States)

    Hollywood, Katherine A; Schmidt, Kamila; Takano, Eriko; Breitling, Rainer

    2018-03-19

    Metabolomics plays an increasingly central role within the Design-Build-Test cycle of synthetic biology, in particular in applications targeting the discovery, diversification and optimised production of a wide range of natural products. For example, improved methods for the online monitoring of chemical reactions accelerate data generation to be compatible with the rapid iterations and increasing library sizes of automated synthetic biology pipelines. Combinations of label-free metabolic profiling and 13 C-based flux analysis lead to increased resolution in the identification of metabolic bottlenecks affecting product yield in engineered microbes. And molecular networking strategies drastically increase our ability to identify and characterise novel chemically complex biomolecules of interest in a diverse range of samples. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Laser accelerators

    International Nuclear Information System (INIS)

    Willis, W.J.

    1977-01-01

    A brief discussion is given on the feasibility of using lasers to accelerate particle beams. A rough theory of operation is developed, and numerical results are obtained for an example equivalent to the Fermilab Accelerator

  19. Method for assessment of stormwater treatment facilities – Synthetic road runoff addition including micro-pollutants and tracer

    DEFF Research Database (Denmark)

    Cederkvist, Karin; Jensen, Marina Bergen; Holm, Peter Engelund

    2017-01-01

    % in the dual porosity filter, stressing the importance of including a conservative tracer for correction of contaminant retention values. The method is considered useful in future treatment performance testing of STFs. The observed performance of the STFs is presented in coming papers.......Stormwater treatment facilities (STFs) are becoming increasingly widespread but knowledge on their performance is limited. This is due to difficulties in obtaining representative samples during storm events and documenting removal of the broad range of contaminants found in stormwater runoff...

  20. High stability of the immunomodulatory GK-1 synthetic peptide measured by a reversed phase high-performance liquid chromatography method.

    Science.gov (United States)

    Cervantes-Torres, Jacquelynne; Segura-Velázquez, René; Padilla, Patricia; Sciutto, Edda; Fragoso, Gladis

    2017-08-15

    The 18-mer anionic peptide GK-1 has been successfully employed to improve the immunogenicity and protective response induced by the influenza vaccine and exhibited some degree of protection against experimental murine melanoma. In this study, a sensitive and quantitative reversed-phase HPLC method was developed to study GK-1 stability under different pH, temperature and storage time. The analysis was carried out on a Sunfire C18 column with mobile phase of acetonitrile-water containing 0.02% TFA. The detection was performed on an UV/Vis Detector at 220nm. The method was validated with respect to linearity, limits of detection and quantification, precision and selectivity. The linear calibration curves were obtained in the concentration range of 0.015-0.24mg/mL (r 2 =0.99) with lower limits of detection (LOD) and quantification (LOQ) of 0.001 and 0.018mg/mL, respectively. The intra- and inter-day precision (relative standard deviation, R.S.D.) values were below 3% at all quality control levels. Forced degradation studies were conducted by introducing a sample of GK-1 peptide standard solution to different conditions of pH (from 2 to 8), temperature (4, 25 and 40°C) and storage time (10days to 6 months). The peptide GK-1 showed to be stable under different ranges of pH and temperature; however it was susceptible to prolonged storage at room temperature. Results shown in this study sustain the high stability of the GK-1 peptide using a reliable new selective and precise method suitable for its analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Synthetic Biology and Personalized Medicine

    Science.gov (United States)

    Jain, K.K.

    2013-01-01

    Synthetic biology, application of synthetic chemistry to biology, is a broad term that covers the engineering of biological systems with structures and functions not found in nature to process information, manipulate chemicals, produce energy, maintain cell environment and enhance human health. Synthetic biology devices contribute not only to improve our understanding of disease mechanisms, but also provide novel diagnostic tools. Methods based on synthetic biology enable the design of novel strategies for the treatment of cancer, immune diseases metabolic disorders and infectious diseases as well as the production of cheap drugs. The potential of synthetic genome, using an expanded genetic code that is designed for specific drug synthesis as well as delivery and activation of the drug in vivo by a pathological signal, was already pointed out during a lecture delivered at Kuwait University in 2005. Of two approaches to synthetic biology, top-down and bottom-up, the latter is more relevant to the development of personalized medicines as it provides more flexibility in constructing a partially synthetic cell from basic building blocks for a desired task. PMID:22907209

  2. Optimization of Catalytic Ozonation Process for Formaldehyde Mineralization from Synthetic Wastewater by Fe/MgO Nanoparticles Synthesis by Sol-Gel Method by Response Surface Model

    Directory of Open Access Journals (Sweden)

    Ghorban Asgari

    2014-09-01

    Full Text Available Background: Design experiment stages of formalin mineralization process by center composition design (CCD cause ease of work, reducing the number of samples, increasing the accuracy of optimized conditions and the interaction parameters determined during the process. The aim of this study was optimization of catalytic ozonation process for formaldehyde mineralization from synthetic wastewater by Fe/MgO nanoparticles synthesis by sol-gel method by response surface model. Methods: This experimental study was conducted in a semi-batch reactor, using a RSM by taking 3 factors in the final stage of pH (7-9, reaction time (10-20 min and catalyst dose (1.1-1.3 g/L was investigated. Synthesis of nanoparticles was done by sol-gel method. The results were analyzed by Design Expert 7.0.1 software. Results: The results showed that the process was dependent on the parameters studied and changing each parameter, affected the process efficiency and other parameters. The optimum conditions predicted for the process was 86.51% of mineralization efficiency. Optimum condition included pH=8.82, reaction time of 20 minute and catalyst dose of 1.3 g/L. The correlation coefficient for the process was determined 0.91. Conclusion: Using a statistical model could reduce the number of experiments, the accuracy and the prediction process. The catalytic ozonation process has the ability to remove formaldehyde with high efficiency and the process was environmental friendly.

  3. Single-shot measurements of low emittance beams from laser-plasma accelerators comparing two triggered injection methods

    Science.gov (United States)

    van Tilborg, Jeroen

    2017-10-01

    The success of laser plasma accelerator (LPA) based applications, such as a compact x-ray free electron laser (FEL), relies on the ability to produce electron beams with excellent 6D brightness, where brightness is defined as the ratio of charge to the product of the three normalized emittances. As such, parametric studies of the emittance of LPA generated electron beams are essential. Profiting from a stable and tunable LPA setup, combined with a carefully designed single-shot energy-dispersed emittance diagnostic, we present a direct comparison of charge dependent emittance measurements of electron beams generated by two different injection mechanisms: ionization injection and shock-induced density down-ramp injection. Both injection mechanisms have gained in popularity in recent years due to their demonstrated stable LPA performance. For the down-ramp injection configuration, normalized emittances a factor of two lower were recorded: less than 1 micron at spectral charge densities up to 2 pC/MeV. For both injection mechanisms, a contributing correlation of space charge to the emittance was identified. This measurement technique in general, and these results specifically, are critical to the evaluation of LPA injection methods and development of high-quality LPA beam lines worldwide. This work is supported by the U.S. DOE under Contract No. DE-AC02-05CH11231, by the U.S. DOE NNSA, DNN R&D (NA22), by the National Science Foundation under Grant No. PHY-1415596, and by the Gordon and Betty Moore Foundation under Grant ID GBMF4898.

  4. Acceleration of radioactive ions

    International Nuclear Information System (INIS)

    Laxdal, R.E.

    2003-01-01

    There is an intense interest world-wide in the use of radioactive ion beams (RIBs) for experiment. In many existing or proposed facilities ions are produced or collected at source potential, ionized and re-accelerated. Within the past year three new ISOL based facilities have added dedicated post-accelerators to deliver accelerated RIBs to experiment. The paper gives an overview of RIB accelerators present and future, and explores the inherent features in the various acceleration methods with an emphasis on heavy ion linacs. The ISAC-I and ISAC-II post-accelerators are discussed as examples. Commissioning results and initial operating experience with ISAC-I will be presented

  5. Accelerators for heavy ions

    International Nuclear Information System (INIS)

    Martin, J.A.

    1975-01-01

    The use of heavy ion accelerators in nuclear physics, nuclear chemistry, atomic physics, and in material sciences studies is rapidly increasing. A review is given of the present and developing scene in heavy ion accelerator concepts and technology. The area of applicability of various methods, likely avenues of future development, and the trends of future requirements are discussed. (auth)

  6. A liquid chromatography-mass spectrometry method based on class characteristic fragmentation pathways to detect the class of indole-derivative synthetic cannabinoids in biological samples.

    Science.gov (United States)

    Mazzarino, Monica; de la Torre, Xavier; Botrè, Francesco

    2014-07-21

    This article describes a liquid chromatographic/tandem mass spectrometric method, based on the use of precursor ion scan as the acquisition mode, specifically developed to detect indole-derived cannabinoids (phenylacetylindoles, naphthoylindoles and benzoylindoles) in biological fluids (saliva, urine and blood). The method is designed to recognize one or more common "structural markers", corresponding to mass spectral fragments originating from the specific portion of the molecular structure that is common to the aminoalkylindole analogues and that is fundamental for their pharmacological classification. As such, the method is also suitable for detecting unknown substances, provided they contain the targeted portion of the molecular structure. The pre-treatment procedure consists in a liquid/liquid extraction step carried out at neutral pH: this is the only pretreatment in the case of analyses carried out in saliva, while it follows an enzymatic hydrolysis procedure in the case of urine samples, or a protein precipitation step in the case of blood samples. The chromatographic separation is achieved using an octadecyl reverse-phase 5 μm fused-core particle column; while the mass spectrometric detection is carried out by a triple-quadrupole instrument in positive electrospray ionization and precursor ion scan as acquisition mode, selecting, as mass spectral fragments, the indole (m/z 144), the carbonylnaphthalenyl (m/z 155) and the naphthalenyl (m/z 127) moieties. Once developed and optimized, the analytical procedure was validated in term of sensitivity (lower limits of detection in the range of 0.1-0.5 ng mL(-1)), specificity (no interference was detected at the retention times of the analytes under investigation), recovery (higher than 65% with a satisfactory repeatability: CV% lower than 10), matrix effect (lower than 30% for all the biological specimens tested), repeatability of the retention times (CV% lower than 0.1), robustness, and carry over (the positive

  7. Jewellery: alloy composition and release of nickel, cobalt and lead assessed with the EU synthetic sweat method.

    Science.gov (United States)

    Hamann, Dathan; Thyssen, Jacob P; Hamann, Carsten R; Hamann, Curtis; Menné, Torkil; Johansen, Jeanne D; Spiewak, Radoslaw; Maibach, Howard; Lundgren, Lennart; Lidén, Carola

    2015-10-01

    Several studies have shown nickel and cobalt release from jewellery by using spot tests, but the metal composition of jewellery is largely unknown. To evaluate the metal composition of a large worldwide sample of mainly inexpensive jewellery items, and investigate the release of nickel, cobalt and lead from a subsample by using EN 1811:1998-required methods. A total of 956 metallic jewellery components were examined with X-ray fluorescence spectroscopy. A subsample of 96 jewellery items purchased in the United States were investigated for nickel, cobalt and lead release by the use of artificial sweat immersion and plasma optical emission spectroscopy. Eighteen elements were detected. The 10 most frequently occurring were, in order of frequency, copper, iron, zinc, nickel, silver, chromium, tin, manganese, lead, and cobalt. Release of nickel was noted from 79 of the 96 US samples (0.01-98 µg/cm(2) /week), release of cobalt from 35 samples (0.02-0.5 µg/cm(2) /week), and release of lead from 37 samples (0.03-2718 µg/cm(2) /week). We present here a comprehensive list of the most frequently encountered metals in jewellery and fashion accessories. Different allergenic and non-allergenic metals are utilized. We also report the frequent release of nickel, cobalt and lead from these objects, despite legislative restrictions. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. [Current development of rapid high-throughout determination technology for total components of traditional Chinese medicines and formula and synthetic immunity chip method].

    Science.gov (United States)

    He, Fu-Yuan; Deng, Kai-Wen; Zeng, Jiao-Li; Dai, Ru-Wen; Dai, Ru-Wen; Xia, Zan-Shao; Liu, Weng-Long; Shi, Ji-Lian

    2012-10-01

    establish the synthetic immunity chip method for traditional Chinese medicine and formula components.

  9. Development of an enzyme-linked immunosorbent assay-based method for measuring galactosyltransferase activity using a synthetic glycopolymer acceptor substrate.

    Science.gov (United States)

    Oubihi, M; Kitajima, K; Kobayashi, K; Adachi, T; Aoki, N; Matsuda, T

    1998-03-15

    A lectin-assisted enzyme-linked immunosorbent assay (ELISA)-based method using a synthetic glycopolymer as an acceptor substrate was developed for measuring beta 1,4-galactosyltransferase (GalT) activity. A polyacrylamide derivative having a beta-linked N-acetylglucosamine (GlcNAc beta) moiety on each monomeric unit was synthesized chemically and immobilized on a polystyrene microtiter plate as an acceptor substrate for GalT. After the plate was incubated with bovine GalT, the enzyme reaction product, beta-linked Gal residue on the polyacrylamide-bound GlcNAc residue, was detected by using Ricinus communis agglutinin 1 (RCA1), rabbit anti-RCA1 antibody, and a peroxidase-labeled anti-rabbit IgG. The lowest GalT concentration detectable by this method was about 0.5 mU/ml, which is comparable to those by the previously reported ELISA-based assays. The unique property of the glycopolymer, PAP(GlcNAc beta), of binding noncovalently but tightly to the polystyrene microtiter plate allowed the use of this acceptor substrate for the GalT activity measurement even in the presence of 1% Triton CF-54 and X-100. Our system was successfully applied to assess GalT activity in milk of various mammals.

  10. Ultrasonic vs hydrothermal method: Different approaches to convert fly ash into zeolite. How they affect the stability of synthetic products over time?

    Science.gov (United States)

    Belviso, Claudia

    2018-05-01

    The action of direct sonication (US) versus conventional hydrothermal method (HY) was investigated to determine the differences in the crystallization mechanism of zeolite formed from fly ash. The results showed that ultrasonic energy is decisive in very fast faujasite and A-type zeolite transformation into more stable sodalite phase. The data display the main presence of sodalite together with a low amount of faujasite and zeolite A after the first 3 h of sonication. The full transformation of the latter two phases into sodalite takes place after 1 h more of treatment. The samples incubated by hydrothermal process for 3 h, instead, are characterized by the main presence of faujasite and A-type zeolites. The progressive synthesis of sodalite at the expense of the other two phases begins only after 4 h of treatment. The conclusion is that the crystallization of zeolites by ultrasonic and hydrothermal method proceeds via two different mechanisms. The data also show that the two approaches affect the stability of the synthetic products in a different way over the years. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Analysis of synthetic cathinones commonly found in bath salts in human performance and postmortem toxicology: method development, drug distribution and interpretation of results.

    Science.gov (United States)

    Marinetti, Laureen J; Antonides, Heather M

    2013-04-01

    To date, the Toxicology Section of the Montgomery County Coroner's Office/Miami Valley Regional Crime Laboratory has identified six synthetic cathinones, commonly found in bath salt products, in 43 cases. Thirty-two cases will be reviewed here, including all of the postmortem cases, all of the human performance cases that had blood specimens submitted, and one urine-only human performance case. The following compounds have been confirmed: 3,4-methylenedioxypyrovalerone (MDPV), 3,4-methylenedioxymethcathinone (methylone), pyrovalerone, pentylone, alpha-pyrrolidinopentiophenone (alpha-PVP) and methedrone. The method also screens for mephedrone, butylone and 3-fluoromethcathinone. Case demographics show 42 white males and females ranging in age from 19 to 53 years. The remaining case was that of a 34-year-old Hispanic male. The 43 cases represent 17 driving under the influence, two domestic violence, four suicides, 12 overdoses, six accidents, one drug-facilitated assault and one homicide. Data will be presented on the distribution of some of these cathinones in various matrices. After review, blood concentration does not appear to predict outcome regarding fatalities or impairment. The highest MDPV concentration occurred in a suicide by hanging and the highest methylone concentration was in a driver. The confirmation method is a liquid-liquid extraction with detection by liquid chromatography triple quadrupole mass spectrometry using electrospray ionization in multiple reaction monitoring mode.

  12. Tissue Harmonic Synthetic Aperture Imaging

    DEFF Research Database (Denmark)

    Rasmussen, Joachim

    The main purpose of this PhD project is to develop an ultrasonic method for tissue harmonic synthetic aperture imaging. The motivation is to advance the field of synthetic aperture imaging in ultrasound, which has shown great potentials in the clinic. Suggestions for synthetic aperture tissue...... system complexity compared to conventional synthetic aperture techniques. In this project, SASB is sought combined with a pulse inversion technique for 2nd harmonic tissue harmonic imaging. The advantages in tissue harmonic imaging (THI) are expected to further improve the image quality of SASB....... The first part of the scientific contribution investigates an implementation of pulse inversion for THI on the experimental ultrasound system SARUS. The technique is initially implemented for linear array transducers and then expanded for convex array transducers. The technique is evaluated based on spatial...

  13. A data processing method for determining instantaneous angular speed and acceleration of crankshaft in an aircraft engine-propeller system using a magnetic encoder

    Science.gov (United States)

    Yu, S. D.; Zhang, X.

    2010-05-01

    This paper presents a method for determining the instantaneous angular speed and instantaneous angular acceleration of the crankshaft in a reciprocating engine and propeller dynamical system from electrical pulse signals generated by a magnetic encoder. The method is based on accurate determination of the measured global mean angular speed and precise values of times when leading edges of individual magnetic teeth pass through the magnetic sensor. Under a steady-state operating condition, a discrete deviation time vs. shaft rotational angle series of uniform interval is obtained and used for accurate determination of the crankshaft speed and acceleration. The proposed method for identifying sub- and super-harmonic oscillations in the instantaneous angular speeds and accelerations is new and efficient. Experiments were carried out on a three-cylinder four-stroke Saito 450R model aircraft engine and a Solo propeller in connection with a 64-teeth Admotec KL2202 magnetic encoder and an HS-4 data acquisition system. Comparisons with an independent data processing scheme indicate that the proposed method yields noise-free instantaneous angular speeds and is superior to the finite difference based methods commonly used in the literature.

  14. Truck acceleration behavior study and acceleration lane length recommendations for metered on-ramps

    OpenAIRE

    Yang, Guangchuan; Xu, Hao; Wang, Zhongren; Tian, Zong

    2016-01-01

    This paper investigated the actual truck acceleration capability at metered on-ramps. Truck acceleration performance data were collected through a video-based data collection method. A piecewise constant acceleration model was employed to capture truck acceleration characteristics. It was found that the existing acceleration length will affect truck drivers’ acceleration behavior. At the taper type ramp that has limited acceleration distance, acceleration profile indicated a decreasing trend ...

  15. Joint Bratislava–Prague studies of radiocarbon and uranium in the environment using accelerator mass spectrometry and radiometric methods

    Czech Academy of Sciences Publication Activity Database

    Povinec, P. P.; Světlík, Ivo; Ješkovský, M.; Sivo, A.; John, J.; Špendlíková, I.; Němec, M.; Kučera, Jan; Richtáriková, M.; Breier, R.; Fejgl, Michal; Černý, Radek

    2015-01-01

    Roč. 304, č. 1 (2015), s. 67-73 ISSN 0236-5731 Institutional support: RVO:61389005 Keywords : Accelerator mass spectrometry * Atmosphere * Environmental radioactivity * Radiocarbon * Tree rings * Uranium Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.983, year: 2015

  16. Engineering survey planning for the alignment of a particle accelerator: part I. Proposition of an assessment method

    Science.gov (United States)

    Junqueira Leão, Rodrigo; Raffaelo Baldo, Crhistian; Collucci da Costa Reis, Maria Luisa; Alves Trabanco, Jorge Luiz

    2018-03-01

    The performance of particle accelerators depends highly on the relative alignment between their components. The position and orientation of the magnetic lenses that form the trajectory of the charged beam is kept to micrometric tolerances in a range of hundreds of meters of the length of the machines. Therefore, the alignment problem is fundamentally of a dimensional metrology nature. There is no common way of expressing these tolerances in terms of terminology and alignment concept. The alignment needs for a certain machine is normally given in terms of deviations between the position of any magnet in the accelerator and the fitted line that relates the actual position of the magnets’ assembly. Root mean square errors and standard deviations are normally used interchangeably and measurement uncertainty is often neglected. Although some solutions have been employed successfully in several accelerators, there is no off-the-shelf solution to perform the alignment. Also, each alignment campaign makes use of different measuring instruments to achieve the desired results, which makes the alignment process a complex measurement chain. This paper explores these issues by reviewing the tolerances specified for the alignment of particle accelerators, and proposes a metric to assess the quality of the alignment. The metric has the advantage of fully integrating the measurement uncertainty in the process.

  17. Laser accelerator

    OpenAIRE

    Vigil, Ricardo

    2014-01-01

    Approved for public release; distribution is unlimited In 1979,W. B. Colson and S. K. Ride proposed a new kind of electron accelerator using a uniform magnetic field in combination with a circularly-polarized laser field. A key concept is to couple the oscillating electric field to the electron’s motion so that acceleration is sustained. This dissertation investigates the performance of the proposed laser accelerator using modern high powered lasers and mag-netic fields that are significan...

  18. Plasma particle accelerators

    International Nuclear Information System (INIS)

    Dawson, J.M.

    1988-01-01

    The Superconducting Supercollider (SSC) will require an 87-kilometer accelerator ring to boost particles to 40 TeV. The SSC's size is due in part to the fact that its operating principle is the same one that has dominated accelerator design for 50 years: it guides particles by means of magnetic fields and propels them by strong electric fields. If one were to build an equally powerful but smaller accelerator, one would need to increase the strength of the guiding and propelling fields. Actually, however, conventional technology may not be able to provide significant increases in field strength. There are two reasons. First, the forces from magnetic fields are becoming greater than the structural forces that hold a magnetic material together; the magnets that produce these fields would themselves be torn apart. Second, the energy from electric fields is reaching the energies that bind electrons to atoms; it would tear electrons from nuclei in the accelerator's support structures. It is the electric field problem that plasma accelerators can overcome. Plasma particle accelerators are based on the principle that particles can be accelerated by the electric fields generated within a plasma. Because the plasma has already been ionized, plasma particle accelerators are not susceptible to electron dissociation. They can in theory sustain accelerating fields thousands of times stronger that conventional technologies. So far two methods for creating plasma waves for accelerators have been proposed and tested: the wakefield and the beat wave. Although promising electric fields have been produced, more research is necessary to determine whether plasma particle accelerators can compete with the existing accelerators. 7 figs

  19. Accelerator development

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Because the use of accelerated heavy ions would provide many opportunities for new and important studies in nuclear physics and nuclear chemistry, as well as other disciplines, both the Chemistry and Physics Divisions are supporting the development of a heavy-ion accelerator. The design of greatest current interest includes a tandem accelerator with a terminal voltage of approximately 25 MV injecting into a linear accelerator with rf superconducting resonators. This combined accelerator facility would be capable of accelerating ions of masses ranging over the entire periodic table to an energy corresponding to approximately 10 MeV/nucleon. This approach, as compared to other concepts, has the advantages of lower construction costs, lower operating power, 100 percent duty factor, and high beam quality (good energy resolution, good timing resolution, small beam size, and small beam divergence). The included sections describe the concept of the proposed heavy-ion accelerator, and the development program aiming at: (1) investigation of the individual questions concerning the superconducting accelerating resonators; (2) construction and testing of prototype accelerator systems; and (3) search for economical solutions to engineering problems. (U.S.)

  20. Impact of the North American Free Trade Agreement on high-fructose corn syrup supply in Canada: a natural experiment using synthetic control methods.

    Science.gov (United States)

    Barlow, Pepita; McKee, Martin; Basu, Sanjay; Stuckler, David

    2017-07-04

    Critics of free trade agreements have argued that they threaten public health, as they eliminate barriers to trade in potentially harmful products, such as sugar. Here we analyze the North American Free Trade Agreement (NAFTA), testing the hypothesis that lowering tariffs on food and beverage syrups that contain high-fructose corn syrup (HFCS) increased its use in foods consumed in Canada. We used supply data from the Food and Agriculture Organization of the United Nations to assess changes in supply of caloric sweeteners including HFCS after NAFTA. We estimate the impact of NAFTA on supply of HFCS in Canada using an innovative, quasi-experimental methodology - synthetic control methods - that creates a control group with which to compare Canada's outcomes. Additional robustness tests were performed for sample, control groups and model specification. Tariff reductions in NAFTA coincided with a 41.6 (95% confidence interval 25.1 to 58.2) kilocalorie per capita daily increase in the supply of caloric sweeteners including HFCS. This change was not observed in the control groups, including Australia and the United Kingdom, as well as a composite control of 16 countries. Results were robust to placebo tests and additional sensitivity analyses. NAFTA was strongly associated with a marked rise in HFCS supply and likely consumption in Canada. Our study provides evidence that even a seemingly modest change to product tariffs in free trade agreements can substantially alter population-wide dietary behaviour and exposure to risk factors. © 2017 Canadian Medical Association or its licensors.

  1. Determination of low isotopic enrichment of L-[1-C-13]valine by gas chromatography combustion isotope ratio mass spectrometry : a robust method for measuring protein fractional synthetic rates in vivo

    NARCIS (Netherlands)

    Reijngoud, DJ; Hellstern, G; Elzinga, H; de Sain-van der Velden, MG; Okken, A; Stellaard, F

    A method was developed for measuring protein fractional synthetic rates using the N-methoxycarbonylmethyl ester (MCM) derivative of L-[1-C-13]valine and on-line gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). The derivatization procedure can be performed rapidly and GC

  2. A method for the simultaneous quantification of eight metabolites of synthetic pyrethroids in urine of the general population using gas chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Schettgen, Thomas; Dewes, Petra; Kraus, Thomas

    2016-08-01

    Synthetic pyrethroids are highly effective, widespread insecticides applied worldwide for different purposes. Among the possible sources of exposure for the general population, pyrethroid residues in food and their prominent use for the conservation of wool carpets or in indoor pest control might play a major role. On the basis of previous works, we have developed and validated a highly sensitive and specific GC/MS/MS-method to simultaneously quantify the metabolites of the most common synthetic pyrethroids in urine, namely cis- and trans-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (DCCA), cis-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylic acid (DBCA), 4-fluoro-3-phenoxybenzoic acid (F-PBA), 3-phenoxybenzoic acid (3-PBA) as well as the metabolites cis-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethyl-cyclopropanecarboxylic acid (ClF3CA, λ-cyhalothrin/bifenthrin), 4-chloro-α-isopropylbenzene acetic acid (CPBA, esfenvalerate), and 2-methyl-3-phenylbenzoic acid (MPB, bifenthrin). After acidic hydrolysis to cleave conjugates in urine, the analytes are subjected to a pH-controlled extraction into n-hexane. After concentration, the analytes are derivatised using MTBSTFA and finally quantified by GC/MS/MS in EI-mode using d6-trans-DCCA and (13)C6-3-PBA as internal standards. The limit of quantification for these metabolites was 0.01 μg/L urine. Precision within and between series was determined to range between 1.6 and 10.7 % using a native quality control sample as well as a urine sample spiked with 0.3 μg/L of the analytes. To investigate possible background excretions, we analysed spot urine samples of 38 persons of the general population in a pilot study. cis- and trans-DCCA as well as 3-PBA could be quantified in every urine sample investigated, while MPB and F-PBA could only be detected in two samples. The median levels for excretion of cis-DCCA, trans-DCCA, 3-PBA, ClF3CA, DBCA, CPBA, F-PBA and MPA were 0.08, 0.17, 0.22, 0.04, 0

  3. Soiling of building envelope surfaces and its effect on solar reflectance – Part III: Interlaboratory study of an accelerated aging method for roofing materials

    Energy Technology Data Exchange (ETDEWEB)

    Sleiman, M; Chen, S; Gilbert, HE; Kirchstetter, TW; Berdahl, P; Bibian, E; Bruckman, LS; Cremona, D; French, RH; Gordon, DA; Emiliani, M; Kable, J; Ma, L; Martarelli, M; Paolini, R; Prestia, M; Renowden, J; Marco Revel, G; Rosseler, O; Shiao, M; Terraneo, G; Yang, T; Yu, L; Zinzi, M; Akbari, H; Levinson, R; Destaillats, H

    2015-09-22

    A laboratory method to simulate natural exposure of roofing materials has been reported in a companion article. Here in the current article, we describe the results of an international, nine-participant interlaboratory study (ILS) conducted in accordance with ASTM Standard E691-09 to establish the precision and reproducibility of this protocol. The accelerated soiling and weathering method was applied four times by each laboratory to replicate coupons of 12 products representing a wide variety of roofing categories (single-ply membrane, factory-applied coating (on metal), bare metal, field-applied coating, asphalt shingle, modified-bitumen cap sheet, clay tile, and concrete tile). Participants reported initial and laboratory-aged values of solar reflectance and thermal emittance. Measured solar reflectances were consistent within and across eight of the nine participating laboratories. Measured thermal emittances reported by six participants exhibited comparable consistency. For solar reflectance, the accelerated aging method is both repeatable and reproducible within an acceptable range of standard deviations: the repeatability standard deviation sr ranged from 0.008 to 0.015 (relative standard deviation of 1.2–2.1%) and the reproducibility standard deviation sR ranged from 0.022 to 0.036 (relative standard deviation of 3.2–5.8%). The ILS confirmed that the accelerated aging method can be reproduced by multiple independent laboratories with acceptable precision. In conclusion, this study supports the adoption of the accelerated aging practice to speed the evaluation and performance rating of new cool roofing materials.

  4. Acceleration of 14C beams in electrostatic accelerators

    International Nuclear Information System (INIS)

    Rowton, L.J.; Tesmer, J.R.

    1981-01-01

    Operational problems in the production and acceleration of 14 C beams for nuclear structure research in Los Alamos National Laboratory's Van de Graaff accelerators are discussed. Methods for the control of contamination in ion sources, accelerators and personnel are described. Sputter source target fabrication techniques and the relative beam production efficiencies of various types of bound particulate carbon sputter source targets are presented

  5. Accelerator for amplification of energy

    International Nuclear Information System (INIS)

    Mori, Yoshiharu

    1998-01-01

    As a forming method of new nuclear energy, an energy amplification system using accelerator driven subcritical reactor is focussed. In order to realize amplification of energy driven by accelerator, development of an accelerator with excellent electric power efficiency is one of the most important problems. The necessary beam power of accelerator is 10 MW, and when reducing used electric power of the accelerator to under 25% of total power generation, more than 30% of electric power efficiency is required for the accelerator. Therefore, an accelerator with excellent electric power efficiency without experiencing before now is required to realize such an aim. A prominent candidate of the accelerator is FFAG (Fixed Field Alternating Gradient) synchrotron (may be called ring synchrotron). In this paper, some simple considerations of electric power efficiency of accelerators and basic parameter of FFAG synchrotron were described. (G.K.)

  6. Diaphragm flange and method for lowering particle beam impedance at connected beam tubes of a particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Biallas, George Herman

    2017-07-04

    A diaphragm flange for connecting the tubes in a particle accelerator while minimizing beamline impedance. The diaphragm flange includes an outer flange and a thin diaphragm integral with the outer flange. Bolt holes in the outer flange provide a means for bolting the diaphragm flange to an adjacent flange or beam tube having a mating bolt-hole pattern. The diaphragm flange includes a first surface for connection to the tube of a particle accelerator beamline and a second surface for connection to a CF flange. The second surface includes a recessed surface therein and a knife-edge on the recessed surface. The diaphragm includes a thickness that enables flexing of the integral diaphragm during assembly of beamline components. The knife-edge enables compression of a soft metal gasket to provide a leak-tight seal.

  7. LIBO accelerates

    CERN Multimedia

    2002-01-01

    The prototype module of LIBO, a linear accelerator project designed for cancer therapy, has passed its first proton-beam acceleration test. In parallel a new version - LIBO-30 - is being developed, which promises to open up even more interesting avenues.

  8. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    accelerator programs. Microsoft runs accelerators in seven different countries. Accelerators have grown out of the infancy stage and are now an accepted approach to develop new ventures based on cutting-edge technology like the internet of things, mobile technology, big data and virtual reality. It is also...... and developing the best business ideas and support the due diligence process. Even universities are noticing that the learning experience of the action learning approach is an effective way to develop capabilities and change cultures. Accelerators related to what has historically been associated...... have the same purpose as businesses: To create customers....

  9. Malignancy of Cancers and Synthetic Lethal Interactions Associated With Mutations of Cancer Driver Genes.

    Science.gov (United States)

    Wang, Xiaosheng; Zhang, Yue; Han, Ze-Guang; He, Kun-Yan

    2016-02-01

    The mutation status of cancer driver genes may correlate with different degrees of malignancy of cancers. The doubling time and multidrug resistance are 2 phenotypes that reflect the degree of malignancy of cancer cells. Because most of cancer driver genes are hard to target, identification of their synthetic lethal partners might be a viable approach to treatment of the cancers with the relevant mutations.The genome-wide screening for synthetic lethal partners is costly and labor intensive. Thus, a computational approach facilitating identification of candidate genes for a focus synthetic lethal RNAi screening will accelerate novel anticancer drug discovery.We used several publicly available cancer cell lines and tumor tissue genomic data in this study.We compared the doubling time and multidrug resistance between the NCI-60 cell lines with mutations in some cancer driver genes and those without the mutations. We identified some candidate synthetic lethal genes to the cancer driver genes APC, KRAS, BRAF, PIK3CA, and TP53 by comparison of their gene phenotype values in cancer cell lines with the relevant mutations and wild-type background. Further, we experimentally validated some of the synthetic lethal relationships we predicted.We reported that mutations in some cancer driver genes mutations in some cancer driver genes such as APC, KRAS, or PIK3CA might correlate with cancer proliferation or drug resistance. We identified 40, 21, 5, 43, and 18 potential synthetic lethal genes to APC, KRAS, BRAF, PIK3CA, and TP53, respectively. We found that some of the potential synthetic lethal genes show significantly higher expression in the cancers with mutations of their synthetic lethal partners and the wild-type counterparts. Further, our experiments confirmed several synthetic lethal relationships that are novel findings by our methods.We experimentally validated a part of the synthetic lethal relationships we predicted. We plan to perform further experiments to validate

  10. Induction accelerators

    CERN Document Server

    Takayama, Ken

    2011-01-01

    A broad class of accelerators rests on the induction principle whereby the accelerating electrical fields are generated by time-varying magnetic fluxes. Particularly suitable for the transport of bright and high-intensity beams of electrons, protons or heavy ions in any geometry (linear or circular) the research and development of induction accelerators is a thriving subfield of accelerator physics. This text is the first comprehensive account of both the fundamentals and the state of the art about the modern conceptual design and implementation of such devices. Accordingly, the first part of the book is devoted to the essential features of and key technologies used for induction accelerators at a level suitable for postgraduate students and newcomers to the field. Subsequent chapters deal with more specialized and advanced topics.

  11. Accelerating Inspire

    CERN Document Server

    AUTHOR|(CDS)2266999

    2017-01-01

    CERN has been involved in the dissemination of scientific results since its early days and has continuously updated the distribution channels. Currently, Inspire hosts catalogues of articles, authors, institutions, conferences, jobs, experiments, journals and more. Successful orientation among this amount of data requires comprehensive linking between the content. Inspire has lacked a system for linking experiments and articles together based on which accelerator they were conducted at. The purpose of this project has been to create such a system. Records for 156 accelerators were created and all 2913 experiments on Inspire were given corresponding MARC tags. Records of 18404 accelerator physics related bibliographic entries were also tagged with corresponding accelerator tags. Finally, as a part of the endeavour to broaden CERN's presence on Wikipedia, existing Wikipedia articles of accelerators were updated with short descriptions and links to Inspire. In total, 86 Wikipedia articles were updated. This repo...

  12. Isochronous cyclotrons. Multicharged ion accelerators

    International Nuclear Information System (INIS)

    Shelaev, I.A.

    1976-01-01

    Isochronous cyclotrons for heavy ions are considered. A development of the heavy ion acceleration technique is discussed. The advantages of heavy ion acceleration by means of the isochronous cyclotron in the energy range up to 10 MeV/nucleon are shown. The requirements to an increase of the beam intensity and decrease of the accelerator dimensions are determined. A considerable increase in the beam intensity is achieved in cascade accelerators of heavy ions. Various schemes of such accelerators are considered, and their parameters are given. To obtain the nuclei with energy of 10 GeV/nucleon and higher, some accelerating complexes are projected, e.g. nuclotrons, where the superconducting magnets are supposed to be used. New methods for heavy ion acceleration are worked out, especially, the collective methods of acceleration

  13. Theoretical problems in accelerator physics

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses the following research on accelerators: computational methods; higher order mode suppression in accelerators structures; overmoded waveguide components and application to SLED II and power transport; rf sources; accelerator cavity design for a B factory asymmetric collider; and photonic band gap cavities

  14. Plant synthetic biology.

    Science.gov (United States)

    Liu, Wusheng; Stewart, C Neal

    2015-05-01

    Plant synthetic biology is an emerging field that combines engineering principles with plant biology toward the design and production of new devices. This emerging field should play an important role in future agriculture for traditional crop improvement, but also in enabling novel bioproduction in plants. In this review we discuss the design cycles of synthetic biology as well as key engineering principles, genetic parts, and computational tools that can be utilized in plant synthetic biology. Some pioneering examples are offered as a demonstration of how synthetic biology can be used to modify plants for specific purposes. These include synthetic sensors, synthetic metabolic pathways, and synthetic genomes. We also speculate about the future of synthetic biology of plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Synthetic antifreeze peptide

    OpenAIRE

    1991-01-01

    A synthetic antifreeze peptide and a synthetic gene coding for the antifreeze peptide have been produced. The antifreeze peptide has a greater number of repeating amino acid sequences than is present in the native antifreeze peptides from winter flounder upon which the synthetic antifreeze peptide was modeled. Each repeating amino acid sequence has two polar amino acid residues which are spaced a controlled distance apart so that the antifreeze peptide may inhibit ice formation. The synthetic...

  16. Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pern, F. J.; Noufi, R.

    2012-10-01

    A step-stress accelerated degradation testing (SSADT) method was employed for the first time to evaluate the stability of CuInGaSe2 (CIGS) solar cells and device component materials in four Al-framed test structures encapsulated with an edge sealant and three kinds of backsheet or moisture barrier film for moisture ingress control. The SSADT exposure used a 15oC and then a 15% relative humidity (RH) increment step, beginning from 40oC/40%RH (T/RH = 40/40) to 85oC/70%RH (85/70) as of the moment. The voluminous data acquired and processed as of total DH = 3956 h with 85/70 = 704 h produced the following results. The best CIGS solar cells in sample Set-1 with a moisture-permeable TPT backsheet showed essentially identical I-V degradation trend regardless of the Al-doped ZnO (AZO) layer thickness ranging from standard 0.12 μm to 0.50 μm on the cells. No clear 'stepwise' feature in the I-V parameter degradation curves corresponding to the SSADT T/RH/time profile was observed. Irregularity in I-V performance degradation pattern was observed with some cells showing early degradation at low T/RH < 55/55 and some showing large Voc, FF, and efficiency degradation due to increased series Rs (ohm-cm2) at T/RH ≥ 70/70. Results of (electrochemical) impedance spectroscopy (ECIS) analysis indicate degradation of the CIGS solar cells corresponded to increased series resistance Rs (ohm) and degraded parallel (minority carrier diffusion/recombination) resistance Rp, capacitance C, overall time constant Rp*C, and 'capacitor quality' factor (CPE-P), which were related to the cells? p-n junction properties. Heating at 85/70 appeared to benefit the CIGS solar cells as indicated by the largely recovered CPE-P factor. Device component materials, Mo on soda lime glass (Mo/SLG), bilayer ZnO (BZO), AlNi grid contact, and CdS/CIGS/Mo/SLG in test structures with TPT showed notable to significant degradation at T/RH ≥ 70/70. At T/RH = 85/70, substantial blistering of

  17. Fast, accurate photon beam accelerator modeling using BEAMnrc: A systematic investigation of efficiency enhancing methods and cross-section data

    Energy Technology Data Exchange (ETDEWEB)

    Fragoso, Margarida; Kawrakow, Iwan; Faddegon, Bruce A.; Solberg, Timothy D.; Chetty, Indrin J. [Henry Ford Health System, Detroit, Michigan 48202 (United States); National Research Council of Canada, Ottawa, Ontario K1A OR6 (Canada); University of California, San Francisco, California 94143-0226 (United States); UT Southwestern Medical Center, Dallas, Texas 75390-9183 (United States); Henry Ford Health System, Detroit, Michigan 48202 (United States)

    2009-12-15

    In this work, an investigation of efficiency enhancing methods and cross-section data in the BEAMnrc Monte Carlo (MC) code system is presented. Additionally, BEAMnrc was compared with VMC++, another special-purpose MC code system that has recently been enhanced for the simulation of the entire treatment head. BEAMnrc and VMC++ were used to simulate a 6 MV photon beam from a Siemens Primus linear accelerator (linac) and phase space (PHSP) files were generated at 100 cm source-to-surface distance for the 10x10 and 40x40 cm{sup 2} field sizes. The BEAMnrc parameters/techniques under investigation were grouped by (i) photon and bremsstrahlung cross sections, (ii) approximate efficiency improving techniques (AEITs), (iii) variance reduction techniques (VRTs), and (iv) a VRT (bremsstrahlung photon splitting) in combination with an AEIT (charged particle range rejection). The BEAMnrc PHSP file obtained without the efficiency enhancing techniques under study or, when not possible, with their default values (e.g., EXACT algorithm for the boundary crossing algorithm) and with the default cross-section data (PEGS4 and Bethe-Heitler) was used as the ''base line'' for accuracy verification of the PHSP files generated from the different groups described previously. Subsequently, a selection of the PHSP files was used as input for DOSXYZnrc-based water phantom dose calculations, which were verified against measurements. The performance of the different VRTs and AEITs available in BEAMnrc and of VMC++ was specified by the relative efficiency, i.e., by the efficiency of the MC simulation relative to that of the BEAMnrc base-line calculation. The highest relative efficiencies were {approx}935 ({approx}111 min on a single 2.6 GHz processor) and {approx}200 ({approx}45 min on a single processor) for the 10x10 field size with 50 million histories and 40x40 cm{sup 2} field size with 100 million histories, respectively, using the VRT directional bremsstrahlung

  18. Recent progress in particle accelerators

    International Nuclear Information System (INIS)

    Cole, F.T.; Mills, F.E.

    1988-01-01

    Many accelerators have also been built for medical radiography and therapy. Electron accelerators for this application are available commercially, using the electrons directly or bremsstrahlung photons. Neutrons produced by accelerator beams have also been used for therapy with considerable success, and several proton accelerators built for physics research have been adapted for direct therapy with protons. The first proton accelerator specifically for therapy is now being built. Separate from what might be called conventional accelerator technology, an entirely new field utilizing very highly pulsed power has been developed, and beams of short pulses of thousands or millions of amperes peak current in the MeV energy range are now available. These beams have important applications in high-energy particle acceleration, controlled fusion, industrial treatment of materials, and possibly in food preservation. All of these accelerators make use of external fields of acceleration. There is also vigorous research into new methods of acceleration, in many schemes making use of the intense accelerating fields, generated by laser beams or by plasma states of matter. This research has not as yet made traditional kinds of accelerators outmoded, but many workers hope that early in the next century there will be practical new acceleration methods making use of these very high fields. These developments are discussed in detail

  19. KEK digital accelerator

    Directory of Open Access Journals (Sweden)

    T. Iwashita

    2011-07-01

    Full Text Available The High Energy Accelerator Research Organization KEK digital accelerator (KEK-DA is a renovation of the KEK 500 MeV booster proton synchrotron, which was shut down in 2006. The existing 40 MeV drift tube linac and rf cavities have been replaced by an electron cyclotron resonance (ECR ion source embedded in a 200 kV high-voltage terminal and induction acceleration cells, respectively. A DA is, in principle, capable of accelerating any species of ion in all possible charge states. The KEK-DA is characterized by specific accelerator components such as a permanent magnet X-band ECR ion source, a low-energy transport line, an electrostatic injection kicker, an extraction septum magnet operated in air, combined-function main magnets, and an induction acceleration system. The induction acceleration method, integrating modern pulse power technology and state-of-art digital control, is crucial for the rapid-cycle KEK-DA. The key issues of beam dynamics associated with low-energy injection of heavy ions are beam loss caused by electron capture and stripping as results of the interaction with residual gas molecules and the closed orbit distortion resulting from relatively high remanent fields in the bending magnets. Attractive applications of this accelerator in materials and biological sciences are discussed.

  20. [SYNTHETIC PEPTIDE VACCINES].

    Science.gov (United States)

    Sergeyev, O V; Barinsky, I F

    2016-01-01

    An update on the development and trials of synthetic peptide vaccines is reviewed. The review considers the successful examples of specific protection as a result of immunization with synthetic peptides using various protocols. The importance of conformation for the immunogenicity of the peptide is pointed out. An alternative strategy of the protection of the organism against the infection using synthetic peptides is suggested.

  1. Development of a method to measure the concentration of 14C in the stack air of nuclear power plants by accelerator mass spectrometry (AMS)

    International Nuclear Information System (INIS)

    Stenstroem, K.; Erlandsson, B.; Hellborg, R.; Haakansson, K.; Wiebert, A.; Skog, G.

    1993-04-01

    C-14, a pure low-energetic beta-emitter, is produced through various nuclear reactions in nuclear power plants. Some of this C-14 is air-borne and is transported via the ventilation system through the stack of the power station and is integrated in living matter in the surroundings of the plant. The long half-life of the isotope (T1/2=5730 years) and the biological importance of carbon may lead to a not negligible contribution of the radiation dose for those living in the neighbourhood of nuclear power plants. C-14 has earlier been measured radiometrically with mainly two different methods, using proportional counters or liquid scintillators. In this report a new method is described, using an accelerator based technique. accelerator mass spectrometry (AMS). This technique has at least three advantages over the radiometrical methods. It requires only a few litres of gas per sample, which is 100-1000 times less compared to the radiometrical methods. It is insensitive to the beta and gamma rays from other radioactive isotopes in the stack air. The measuring time with AMS, about 20 minutes per sample, is considerably shorter compared to the radiometrical methods, which demand several hours per sample. The integrity of the AMS method is high and it might be convenient for regulatory supervision. (22 refs.)

  2. FMIT accelerator

    International Nuclear Information System (INIS)

    Armstrong, D.D.

    1983-01-01

    A 35-MeV 100-mA cw linear accelerator is being designed by Los Alamos for use in the Fusion Materials Irradiation Test (FMIT) Facility. Essential to this program is the design, construction, and evaluation of performance of the accelerator's injector, low-energy beam transport, and radio-frequency quadrupole sections before they are shipped to the facility site. The installation and testing of some of these sections have begun as well as the testing of the rf, noninterceptive beam diagnostics, computer control, dc power, and vacuum systems. An overview of the accelerator systems and the performance to date is given

  3. Development and validation of a high-resolution mass-spectrometry-based method to study the long-term stability of natural and synthetic glucocorticoids in faeces.

    Science.gov (United States)

    De Clercq, Nathalie; Vanden Bussche, Julie; Croubels, Siska; Delahaut, Philippe; Vanhaecke, Lynn

    2014-04-04

    Faecal glucocorticoid analysis is a powerful non-invasive tool for the study of the animal endocrine status and stress physiology, which is mainly carried out by immunoassays, characterised by some limitations. In this study, an ultra high-performance liquid chromatography coupled to high resolution Orbitrap mass spectrometry (U-HPLC-HRMS) method was developed to confirm the presence of glucocorticoids in bovine faeces during a long-term stability study. Because of the complex nature of faeces, an appropriate extraction and purification procedure was developed. To this extent, a Plackett-Burman experimental design was successfully applied to determine the key conditions for optimal extraction of glucocorticoids from faeces. The targeted analysis, including natural and synthetic glucocorticoids, was successfully validated according to CD 2002/657/EC. Decision limits and detection capabilities for prednisolone, prednisone, methylprednisolone and the metabolites 20α-dihydroprednisolone and 20β-dihydroprednisolone ranged, respectively, from 0.15 to 2.95 μg kg(-1) and from 0.40 to 5.20 μg kg(-1). Limits of detection and limits of quantification for the natural glucocorticoids dihydrocortisone, cortisol and cortisone ranged, respectively, from 0.55 to 2.10 μg kg(-1) and from 0.70 to 5.00 μg kg(-1). The stability study of glucocorticoids in faecal matrix demonstrated that lyophilising the faeces, storage at -80°C, and aerobic conditions were optimal for preservation and able to significantly (p < 0.05) limit degradation up to 10 weeks. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Advanced Accelerator Concepts

    Science.gov (United States)

    Siemann, Robert

    1998-04-01

    Current particle accelerators rely on conventional or superconducting radio frequency cavities to accelerate beams of protons or electrons for nuclear and particle research and for medical and materials science studies. New methods for achieving larger accelerating gradients have been proposed and are being studied. These include the use of high power lasers, laser driven plasmas, wake fields generated by intense low energy beams, and millimeter wavelength EM structures. The studies to date, and the prospects for practical applications of these new ideas will be discussed.

  5. Horizontal Accelerator

    Data.gov (United States)

    Federal Laboratory Consortium — The Horizontal Accelerator (HA) Facility is a versatile research tool available for use on projects requiring simulation of the crash environment. The HA Facility is...

  6. Method to prevent ejecta from damaging the Compact Torus Accelerator driver of an inertial fusion energy power plant

    International Nuclear Information System (INIS)

    Mattingly, S.E.K.; Moir, R.W.

    1992-01-01

    Concern has been expressed about the conceptual design of fusion reactors using a Compact Torus Accelerator (CTA). A CTA accelerates a plasma torus toward a fusion target. When the torus nears the target, it is compressed and focused down to a small volume, creating a very high energy density and initiating a fusion micro explosion. The focusing cone is destroyed with each shot due to the stress from the passage of the torus as well as from the force of the explosion (1 800 MJ of yield, ∼0.5 Ton TNT equivalent). The focusing cone could be made of solidified Li 2 BeF 4 ; the same material used in liquid state to protect the reaction chamber from the micro explosion and to transport heat away to a power plant. The problem with this design is that when the focusing cone is shattered, the resulting small pieces of solid and liquid debris (ejecta) might be carded along by the expanding vapor of the explosion and might enter the CTA itself, causing damage and shortening the life of the CTA. The proposed solution for this possible problem is to bend the focusing cone so that the ejecta no longer have a clear path to the CTA. Calculations show that the plasma torus may be sent through a radius of curvature of less than 0.5 m just after the focusing cone, without significantly disturbing the plasma

  7. Effectiveness of non-conventional methods for accelerated orthodontic tooth movement: a systematic review and meta-analysis.

    Science.gov (United States)

    Gkantidis, Nikolaos; Mistakidis, Ilias; Kouskoura, Thaleia; Pandis, Nikolaos

    2014-10-01

    To assess the available evidence on the effectiveness of accelerated orthodontic tooth movement through surgical and non-surgical approaches in orthodontic patients. Randomized controlled trials and controlled clinical trials were identified through electronic and hand searches (last update: March 2014). Orthognathic surgery, distraction osteogenesis, and pharmacological approaches were excluded. Risk of bias was assessed using the Cochrane risk of bias tool. Eighteen trials involving 354 participants were included for qualitative and quantitative synthesis. Eight trials reported on low-intensity laser, one on photobiomodulation, one on pulsed electromagnetic fields, seven on corticotomy, and one on interseptal bone reduction. Two studies on corticotomy and two on low-intensity laser, which had low or unclear risk of bias, were mathematically combined using the random effects model. Higher canine retraction rate was evident with corticotomy during the first month of therapy (WMD=0.73; 95% CI: 0.28, 1.19, ppulsed electromagnetic fields. Overall, the results should be interpreted with caution given the small number, quality, and heterogeneity of the included studies. Further research is required in this field with additional attention to application protocols, adverse effects, and cost-benefit analysis. From the qualitative and quantitative synthesis of the studies, it could be concluded that there is some evidence that low laser therapy and corticotomy are associated with accelerated orthodontic tooth movement, while further investigation is required before routine application. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Geo synthetic-reinforced Pavement systems

    International Nuclear Information System (INIS)

    Zornberg, J. G.

    2014-01-01

    Geo synthetics have been used as reinforcement inclusions to improve pavement performance. while there are clear field evidence of the benefit of using geo synthetic reinforcements, the specific conditions or mechanisms that govern the reinforcement of pavements are, at best, unclear and have remained largely unmeasured. Significant research has been recently conducted with the objectives of: (i) determining the relevant properties of geo synthetics that contribute to the enhanced performance of pavement systems, (ii) developing appropriate analytical, laboratory and field methods capable of quantifying the pavement performance, and (iii) enabling the prediction of pavement performance as a function of the properties of the various types of geo synthetics. (Author)

  9. Soiling of building envelope surfaces and its effect on solar reflectance – Part II: Development of an accelerated aging method for roofing materials

    Energy Technology Data Exchange (ETDEWEB)

    Sleiman, Mohamad [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kirchstetter, Thomas W. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Berdahl, Paul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gilbert, Haley E. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Quelen, Sarah [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Marlot, Lea [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Preble, Chelsea V. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Chen, Sharon [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Montalbano, Amandine [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rosseler, Olivier [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Akbari, Hashem [Concordia Univ., Montreal (Canada); Levinson, Ronnen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Destaillats, Hugo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-01-09

    Highly reflective roofs can decrease the energy required for building air conditioning, help mitigate the urban heat island effect, and slow global warming. However, these benefits are diminished by soiling and weathering processes that reduce the solar reflectance of most roofing materials. Soiling results from the deposition of atmospheric particulate matter and the growth of microorganisms, each of which absorb sunlight. Weathering of materials occurs with exposure to water, sunlight, and high temperatures. This study developed an accelerated aging method that incorporates features of soiling and weathering. The method sprays a calibrated aqueous soiling mixture of dust minerals, black carbon, humic acid, and salts onto preconditioned coupons of roofing materials, then subjects the soiled coupons to cycles of ultraviolet radiation, heat and water in a commercial weatherometer. Three soiling mixtures were optimized to reproduce the site-specific solar spectral reflectance features of roofing products exposed for 3 years in a hot and humid climate (Miami, Florida); a hot and dry climate (Phoenix, Arizona); and a polluted atmosphere in a temperate climate (Cleveland, Ohio). A fourth mixture was designed to reproduce the three-site average values of solar reflectance and thermal emittance attained after 3 years of natural exposure, which the Cool Roof Rating Council (CRRC) uses to rate roofing products sold in the US. This accelerated aging method was applied to 25 products₋single ply membranes, factory and field applied coatings, tiles, modified bitumen cap sheets, and asphalt shingles₋and reproduced in 3 days the CRRC's 3-year aged values of solar reflectance. In conclusion, this accelerated aging method can be used to speed the evaluation and rating of new cool roofing materials.

  10. Control theory meets synthetic biology.

    Science.gov (United States)

    Del Vecchio, Domitilla; Dy, Aaron J; Qian, Yili

    2016-07-01

    The past several years have witnessed an increased presence of control theoretic concepts in synthetic biology. This review presents an organized summary of how these control design concepts have been applied to tackle a variety of problems faced when building synthetic biomolecular circuits in living cells. In particular, we describe success stories that demonstrate how simple or more elaborate control design methods can be used to make the behaviour of synthetic genetic circuits within a single cell or across a cell population more reliable, predictable and robust to perturbations. The description especially highlights technical challenges that uniquely arise from the need to implement control designs within a new hardware setting, along with implemented or proposed solutions. Some engineering solutions employing complex feedback control schemes are also described, which, however, still require a deeper theoretical analysis of stability, performance and robustness properties. Overall, this paper should help synthetic biologists become familiar with feedback control concepts as they can be used in their application area. At the same time, it should provide some domain knowledge to control theorists who wish to enter the rising and exciting field of synthetic biology. © 2016 The Author(s).

  11. Optimization of the reversed-phase high-performance liquid chromatographic separation of synthetic estrogenic and progestogenic steroids using the multi-criteria decision making method

    NARCIS (Netherlands)

    Smilde, A. K.; Bruins, C. H.; Doornbos, D. A.; Vink, J.

    1987-01-01

    The optimization of the reversed-phase high-performance liquid chromatographic separation of a mixture of ethynylestradiol, desogestrel and three related compounds is described. A procedure is used that allows the prediction of the capacity factors of each individual synthetic steroid, depending on

  12. properties of the SN - equivalent integral transport operator in slab geometry and the iterative acceleration of neutron transport methods

    International Nuclear Information System (INIS)

    Massimiliano, Rosa; Azmy, Y.Y.; Morel, J.E.

    2005-01-01

    The general expressions for the matrix elements of the discrete Sn-equivalent integral transport operator have been derived in slab geometry. Their asymptotic behavior has been investigated both for a homogeneous slab and for a heterogeneous slab characterized by a periodic material discontinuity wherein each optically thick cell is surrounded by two optically thin cells in a repeating pattern. In the case of a homogeneous slab, the asymptotic analysis conducted in a diffusive limit obtained as the thick limit of computational cell size for a highly scattering medium, has shown that the discretized integral transport operator is approximated by a sparse matrix characterized by a tri-diagonal diffusion-like coupling stencil. Also, the tri-diagonal matrix structure, characteristic of the diffusion coupling stencil, is approached at a fast exponential rate. In the case of periodically heterogeneous slab configurations, the asymptotic behavior investigated is that in which the cells' optical thicknesses are pushed apart, i.e. the thick is made thicker while the thin is made thinner at a prescribed rate. It has been shown that in this limit the discretized integral transport operator is approximated by a penta-diagonal structure. Notwithstanding, the discrete operator is amenable to algebraic transformations leading to a matrix representation still asymptotically approaching a tri-diagonal structure at a fast exponential rate. The existence of a low order tri-diagonal approximation to the full discrete integral transport operator in the case of a periodically heterogeneous slab might provide a basic understanding of the superior convergence properties of diffusion-based acceleration schemes observed in slab geometry, even in the presence of sharp material discontinuities. The obtained results also suggest that a sparse approximation to the S n -equivalent integral transport operator might itself be used as the low-order operator in an acceleration scheme for the

  13. Thermographic Method Based Accelerated Fatigue Limit Calculation for Steel X5CrNi18-10 Subjected to Rotating Bending

    Directory of Open Access Journals (Sweden)

    Lipski Adam

    2015-12-01

    Full Text Available The article presents an accelerated method for fatigue limit calculation which makes use of constant temperature increase rate observed in the middle time interval of specimen fatigue loading. The examination was performed on specimens prepared from drawn rods made of corrosion resistant austenitic steel X5CrNi18-10 (1.4301 subjected to rotating bending. For comparison purposes, the fatigue limit was also calculated with the aid of the Staircase method, using 30 specimens and assuming the base number of cycles equal to 10·106. Three specimens were used for accelerated examination during which their temperature was measured with the aid of the thermographic camera CEDIP Silver 420M (FLIR SC 5200. The applied loads were gradually increased until specimen damage took place. Based on the analysis of temperature changes during specimen loading, the average rate of temperature increase at successive loading stages was assessed. The obtained results were then approximated using the 2-nd order curve and its minimal value was assumed as corresponding to the fatigue limit. The performed statistic test has revealed that the fatigue limit calculated in the above way does not differ substantially from that determined using the Staircase method.

  14. Particle acceleration by collective effects

    International Nuclear Information System (INIS)

    Keefe, D.

    1976-01-01

    Successful acceleration of protons and other ions has been achieved experimentally in this decade by a number of different collective methods. The attainment of very high accelerating fields has been established although so far the acceleration distance has been confined to only a few centimeters. Efforts are in progress to understand the accelerating mechanisms in detail and, as a result, to devise ways of extending considerably the acceleration distance. This paper is intended to review the current progress, expectations, and limitations of the different approaches. (author)

  15. Electron accelerators for environmental protection

    International Nuclear Information System (INIS)

    Zimek, Z.

    1998-01-01

    The primary objective of this publication is to provide information suitable for electron accelerators implementation in facilities applying radiation technology for environmental protection. It should be noticed that radiation processing has been successfully used in the fields of crosslinking polymer curing and medical products sterilization for more than 40 years. Practical application of radiation technology today extends on SO 2 and NO x removal from the flue gas (one of major power intensive radiation processing), destruction and removal of organic chemicals from water, decreasing bacteria content in the irradiated sludge and waste water. On the other hand the increased awareness of environmental pollution hazards and more stringent waste regulations in many countries may open stronger support for environmentally oriented technologies. This publication provides an evaluation of electron accelerators capabilities in respect of environmental applications where technological and economical criteria are now well defined. In order to determine the potential of electron accelerators, the literature data were examined as well visits and meetings with various accelerator manufacturers were performed by the author. Experience of the author in accelerator facilities construction and exploitation including those which were used for environmental protection are significant part of this publication. The principle of accelerator action was described in Chapter 1. Early development, accelerator classification and fields of accelerators application were included to this chapter as well. Details of accelerator construction was described in Chapter 2 to illustrate physical capability of accelerators to perform the function of ionizing radiation source. Electron beam extraction devices, under beam equipment, electron beam parameters and measuring methods were characterized in this chapter as well. Present studies of accelerator technology was described in Chapter 3, where

  16. Accelerator microanalysis

    International Nuclear Information System (INIS)

    Tuniz, C.

    1997-01-01

    Particle accelerators have been developed more than sixty years ago to investigate nuclear and atomic phenomena. A major shift toward applications of accelerators in the study of materials structure and composition in inter-disciplinary projects has been witnessed in the last two decades. The Australian Nuclear Science and Technology Organisation (ANSTO) has developed advanced research programs based on the use of particle and photon beams. Atmospheric pollution problems are investigated at the 3 MV Van de Graff accelerator using ion beam analysis techniques to detect toxic elements in aerosol particles. High temperature superconductor and semiconductor materials are characterised using the recoil of iodine and other heavy ions produced at ANTARES, the 10-MV Tandem accelerator. A heavy-ion microprobe is presently being developed at ANTARES to map elemental concentrations of specific elements with micro-size resolution. An Accelerator mass Spectrometry (AMS) system has been developed at ANSTO for the ultra-sensitive detection of Carbon-14, Iodine-129 and other long-lived radioisotopes. This AMS spectrometer is a key instrument for climate change studies and international safeguards. ANSTO is also managing the Australian Synchrotron Research program based on facilities developed at the Photon Factory (Japan) and at the Advanced Photon Source (USA). Advanced projects in biology, materials chemistry, structural condensed matter and other disciplines are being promoted by a consortium involving Australian universities and research institutions. This paper will review recent advances in the use of particle accelerators, with a particular emphasis on applications developed at ANSTO and related to problems of international concern, such as global environmental change, public health and nuclear proliferation

  17. [From synthetic biology to synthetic humankind].

    Science.gov (United States)

    Nouvel, Pascal

    2015-01-01

    In this paper, we propose an historical survey of the expression "synthetic biology" in order to identify its main philosophical components. The result of the analysis is then used to investigate the meaning of the notion of "synthetic man". It is shown that both notions share a common philosophical background that can be summed up by the short but meaningful assertion: "biology is technology". The analysis allows us to distinguish two notions that are often confused in transhumanist literature: the notion of synthetic man and the notion of renewed man. The consequences of this crucial distinction are discussed. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  18. Synthetic Cathinones ("Bath Salts")

    Science.gov (United States)

    ... cathinones? Behavioral therapy can be used to treat addiction to synthetic cathinones. Examples include: cognitive-behavioral therapy contingency management, or motivational incentives—providing rewards to ...

  19. US Competitiveness in Synthetic Biology.

    Science.gov (United States)

    Gronvall, Gigi Kwik

    2015-01-01

    Synthetic biology is an emerging technical field that aims to make biology easier to engineer; the field has applications in strategically important sectors for the US economy. While the United States currently leads in synthetic biology R&D, other nations are heavily investing in order to boost their economies, which will inevitably diminish the US leadership position. This outcome is not entirely negative--additional investments will expand markets--but it is critical that the US government take steps to remain competitive: There are applications from which the US population and economy may benefit; there are specific applications with importance for national defense; and US technical leadership will ensure that US experts have a leading role in synthetic biology governance, regulation, and oversight. Measures to increase competitiveness in S&T generally are broadly applicable for synthetic biology and should be pursued. However, the US government will also need to take action on fundamental issues that will affect the field's development, such as countering anti-GMO (genetically modified organism) sentiments and anti-GMO legislation. The United States should maintain its regulatory approach so that it is the product that is regulated, not the method used to create a product. At the same time, the United States needs to ensure that the regulatory framework is updated so that synthetic biology products do not fall into regulatory gaps. Finally, the United States needs to pay close attention to how synthetic biology applications may be governed internationally, such as through the Nagoya Protocol of the Convention on Biological Diversity, so that beneficial applications may be realized.

  20. Synthetic Aperture Vector Flow Imaging

    DEFF Research Database (Denmark)

    Oddershede, Niels

    2008-01-01

    of the thesis considers a method for estimating the two-dimensional velocity vector within the image plane. This method, called synthetic aperture vector flow imaging, is first shortly reviewed. The main contribution of this work is partly an analysis of the method with respect to focusing effects, motion...... estimation. The method can be used for increasing the frame rate of color flow maps or alternatively for a new imaging modality entitled quadroplex imaging, featuring a color flow map and two independent spectrograms at a high frame rate. The second is an alternative method for ultrasonic vector velocity...

  1. Mapping the Information Trace in Local Field Potentials by a Computational Method of Two-Dimensional Time-Shifting Synchronization Likelihood Based on Graphic Processing Unit Acceleration.

    Science.gov (United States)

    Zhao, Zi-Fang; Li, Xue-Zhu; Wan, You

    2017-12-01

    The local field potential (LFP) is a signal reflecting the electrical activity of neurons surrounding the electrode tip. Synchronization between LFP signals provides important details about how neural networks are organized. Synchronization between two distant brain regions is hard to detect using linear synchronization algorithms like correlation and coherence. Synchronization likelihood (SL) is a non-linear synchronization-detecting algorithm widely used in studies of neural signals from two distant brain areas. One drawback of non-linear algorithms is the heavy computational burden. In the present study, we proposed a graphic processing unit (GPU)-accelerated implementation of an SL algorithm with optional 2-dimensional time-shifting. We tested the algorithm with both artificial data and raw LFP data. The results showed that this method revealed detailed information from original data with the synchronization values of two temporal axes, delay time and onset time, and thus can be used to reconstruct the temporal structure of a neural network. Our results suggest that this GPU-accelerated method can be extended to other algorithms for processing time-series signals (like EEG and fMRI) using similar recording techniques.

  2. New methods for optical distance indicator and gantry angle quality control tests in medical linear accelerators: image processing by using a 3D phantom

    International Nuclear Information System (INIS)

    Shandiz, Mahdi Heravian; Khalilzadeh, Mohammadmahdi; Anvari, Kazem; Layen, Ghorban Safaeian

    2015-01-01

    In order to keep the acceptable level of the radiation oncology linear accelerators, it is necessary to apply a reliable quality assurance (QA) program. The QA protocols, published by authoritative organizations, such as the American Association of Physicists in Medicine (AAPM), determine the quality control (QC) tests which should be performed on the medical linear accelerators and the threshold levels for each test. The purpose of this study is to increase the accuracy and precision of the selected QC tests in order to increase the quality of treatment and also increase the speed of the tests to convince the crowded centers to start a reliable QA program. A new method has been developed for two of the QC tests; optical distance indicator (ODI) QC test as a daily test and gantry angle QC test as a monthly test. This method uses an image processing approach utilizing the snapshots taken by the CCD camera to measure the source to surface distance (SSD) and gantry angle. The new method of ODI QC test has an accuracy of 99.95% with a standard deviation of 0.061 cm and the new method for gantry angle QC has a precision of 0.43 degrees. The automated proposed method which is used for both ODI and gantry angle QC tests, contains highly accurate and precise results which are objective and the human-caused errors have no effect on the results. The results show that they are in the acceptable range for both of the QC tests, according to AAPM task group 142.

  3. New methods for optical distance indicator and gantry angle quality control tests in medical linear accelerators: image processing by using a 3D phantom

    Energy Technology Data Exchange (ETDEWEB)

    Shandiz, Mahdi Heravian; Khalilzadeh, Mohammadmahdi; Anvari, Kazem [Mashhad Branch, Islamic Azad University, Mashhad (Iran, Islamic Republic of); Layen, Ghorban Safaeian [Mashhad University of Medical Science, Mashhad (Iran, Islamic Republic of)

    2015-03-15

    In order to keep the acceptable level of the radiation oncology linear accelerators, it is necessary to apply a reliable quality assurance (QA) program. The QA protocols, published by authoritative organizations, such as the American Association of Physicists in Medicine (AAPM), determine the quality control (QC) tests which should be performed on the medical linear accelerators and the threshold levels for each test. The purpose of this study is to increase the accuracy and precision of the selected QC tests in order to increase the quality of treatment and also increase the speed of the tests to convince the crowded centers to start a reliable QA program. A new method has been developed for two of the QC tests; optical distance indicator (ODI) QC test as a daily test and gantry angle QC test as a monthly test. This method uses an image processing approach utilizing the snapshots taken by the CCD camera to measure the source to surface distance (SSD) and gantry angle. The new method of ODI QC test has an accuracy of 99.95% with a standard deviation of 0.061 cm and the new method for gantry angle QC has a precision of 0.43 degrees. The automated proposed method which is used for both ODI and gantry angle QC tests, contains highly accurate and precise results which are objective and the human-caused errors have no effect on the results. The results show that they are in the acceptable range for both of the QC tests, according to AAPM task group 142.

  4. Accelerator operations

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Operations of the SuperHILAC, the Bevatron/Bevalac, and the 184-inch Synchrocyclotron during the period from October 1977 to September 1978 are discussed. These include ion source development, accelerator facilities, the Heavy Ion Spectrometer System, and Bevelac biomedical operations

  5. Acceleration grid

    International Nuclear Information System (INIS)

    Hemmerich, J.; Kupschus, P.; Fraenkle, H.

    1983-01-01

    The acceleration grid is used in nuclear fusion technique as an ion beam grid. It consists of perforated plates at different potentials situated behind one another in the axial movement direction of their through holes. In order to prevent interference in the perforated hole area due to thermal expansion, the perforated plates are fixed with elastic springiness (plate fields) at their edges. (DG) [de

  6. Accelerators course

    CERN Multimedia

    CERN. Geneva HR-RFA; Métral, E

    2006-01-01

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges

  7. Accelerator operations

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    This section is concerned with the operation of both the tandem-linac system and the Dynamitron, two accelerators that are used for entirely different research. Developmental activities associated with the tandem and the Dynamitron are also treated here, but developmental activities associated with the superconducting linac are covered separately because this work is a program of technology development in its own right

  8. Accelerator update

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    When the Accelerator Conference, combined International High Energy and US Particle versions, held in Dallas in May, was initially scheduled, progress nearby for the US Superconducting Supercollider was high on the preliminary agenda. With the SSC voted down by Congress in October 1993, this was no longer the case. However the content of the meeting, in terms of both its deep implications for ambitious new projects and the breadth of its scope, showed that the worldwide particle accelerator field is far from being moribund. A traditional feature of such accelerator conferences is the multiplicity of parallel sessions. No one person can attend all sessions, so that delegates can follow completely different paths and emerge with totally different impressions. Despite this overload, and despite the SSC cancellation, the general picture is one of encouraging progress over a wide range of major new projects throughout the world. At the same time, spinoff from, and applications of, accelerators and accelerator technology are becoming increasingly important. Centrestage is now CERN's LHC proton-proton collider, where a test string of superconducting magnets is operating over long periods at the nominal LHC field of 8.36 tesla or more. The assignment of the underground areas in the existing 27- kilometre LEP tunnel is now quasidefinitive (see page 3). For CERN's existing big machine, the LEP electron-positron collider, ongoing work concentrates on boosting performance using improved optics and bunch trains. But the main objective is the LEP2 scheme using superconducting accelerating cavities to boost the beam energy (see page 6). After some initial teething problems, production and operation of these cavities appears to have been mastered, at least under test conditions. A highlight at CERN last year was the first run with lead ions (December 1994, page 15). Handling these heavy particles with systems originally designed for protons calls for ingenuity. The SPS

  9. Multilevel acceleration of scattering-source iterations with application to electron transport

    Directory of Open Access Journals (Sweden)

    Clif Drumm

    2017-09-01

    Full Text Available Acceleration/preconditioning strategies available in the SCEPTRE radiation transport code are described. A flexible transport synthetic acceleration (TSA algorithm that uses a low-order discrete-ordinates (SN or spherical-harmonics (PN solve to accelerate convergence of a high-order SN source-iteration (SI solve is described. Convergence of the low-order solves can be further accelerated by applying off-the-shelf incomplete-factorization or algebraic-multigrid methods. Also available is an algorithm that uses a generalized minimum residual (GMRES iterative method rather than SI for convergence, using a parallel sweep-based solver to build up a Krylov subspace. TSA has been applied as a preconditioner to accelerate the convergence of the GMRES iterations. The methods are applied to several problems involving electron transport and problems with artificial cross sections with large scattering ratios. These methods were compared and evaluated by considering material discontinuities and scattering anisotropy. Observed accelerations obtained are highly problem dependent, but speedup factors around 10 have been observed in typical applications.

  10. Identification of potential small molecule allosteric modulator sites on IL-1R1 ectodomain using accelerated conformational sampling method.

    Directory of Open Access Journals (Sweden)

    Chao-Yie Yang

    Full Text Available The interleukin-1 receptor (IL-1R is the founding member of the interleukin 1 receptor family which activates innate immune response by its binding to cytokines. Reports showed dysregulation of cytokine production leads to aberrant immune cells activation which contributes to auto-inflammatory disorders and diseases. Current therapeutic strategies focus on utilizing antibodies or chimeric cytokine biologics. The large protein-protein interaction interface between cytokine receptor and cytokine poses a challenge in identifying binding sites for small molecule inhibitor development. Based on the significant conformational change of IL-1R type 1 (IL-1R1 ectodomain upon binding to different ligands observed in crystal structures, we hypothesized that transient small molecule binding sites may exist when IL-1R1 undergoes conformational transition and thus suitable for inhibitor development. Here, we employed accelerated molecular dynamics (MD simulation to efficiently sample conformational space of IL-1R1 ectodomain. Representative IL-1R1 ectodomain conformations determined from the hierarchy cluster analysis were analyzed by the SiteMap program which leads to identify small molecule binding sites at the protein-protein interaction interface and allosteric modulator locations. The cosolvent mapping analysis using phenol as the probe molecule further confirms the allosteric modulator site as a binding hotspot. Eight highest ranked fragment molecules identified from in silico screening at the modulator site were evaluated by MD simulations. Four of them restricted the IL-1R1 dynamical motion to inactive conformational space. The strategy from this study, subject to in vitro experimental validation, can be useful to identify small molecule compounds targeting the allosteric modulator sites of IL-1R and prevent IL-1R from binding to cytokine by trapping IL-1R in inactive conformations.

  11. Identification of potential small molecule allosteric modulator sites on IL-1R1 ectodomain using accelerated conformational sampling method.

    Science.gov (United States)

    Yang, Chao-Yie

    2015-01-01

    The interleukin-1 receptor (IL-1R) is the founding member of the interleukin 1 receptor family which activates innate immune response by its binding to cytokines. Reports showed dysregulation of cytokine production leads to aberrant immune cells activation which contributes to auto-inflammatory disorders and diseases. Current therapeutic strategies focus on utilizing antibodies or chimeric cytokine biologics. The large protein-protein interaction interface between cytokine receptor and cytokine poses a challenge in identifying binding sites for small molecule inhibitor development. Based on the significant conformational change of IL-1R type 1 (IL-1R1) ectodomain upon binding to different ligands observed in crystal structures, we hypothesized that transient small molecule binding sites may exist when IL-1R1 undergoes conformational transition and thus suitable for inhibitor development. Here, we employed accelerated molecular dynamics (MD) simulation to efficiently sample conformational space of IL-1R1 ectodomain. Representative IL-1R1 ectodomain conformations determined from the hierarchy cluster analysis were analyzed by the SiteMap program which leads to identify small molecule binding sites at the protein-protein interaction interface and allosteric modulator locations. The cosolvent mapping analysis using phenol as the probe molecule further confirms the allosteric modulator site as a binding hotspot. Eight highest ranked fragment molecules identified from in silico screening at the modulator site were evaluated by MD simulations. Four of them restricted the IL-1R1 dynamical motion to inactive conformational space. The strategy from this study, subject to in vitro experimental validation, can be useful to identify small molecule compounds targeting the allosteric modulator sites of IL-1R and prevent IL-1R from binding to cytokine by trapping IL-1R in inactive conformations.

  12. SU-E-T-493: Accelerated Monte Carlo Methods for Photon Dosimetry Using a Dual-GPU System and CUDA.

    Science.gov (United States)

    Liu, T; Ding, A; Xu, X

    2012-06-01

    To develop a Graphics Processing Unit (GPU) based Monte Carlo (MC) code that accelerates dose calculations on a dual-GPU system. We simulated a clinical case of prostate cancer treatment. A voxelized abdomen phantom derived from 120 CT slices was used containing 218×126×60 voxels, and a GE LightSpeed 16-MDCT scanner was modeled. A CPU version of the MC code was first developed in C++ and tested on Intel Xeon X5660 2.8GHz CPU, then it was translated into GPU version using CUDA C 4.1 and run on a dual Tesla m 2 090 GPU system. The code was featured with automatic assignment of simulation task to multiple GPUs, as well as accurate calculation of energy- and material- dependent cross-sections. Double-precision floating point format was used for accuracy. Doses to the rectum, prostate, bladder and femoral heads were calculated. When running on a single GPU, the MC GPU code was found to be ×19 times faster than the CPU code and ×42 times faster than MCNPX. These speedup factors were doubled on the dual-GPU system. The dose Result was benchmarked against MCNPX and a maximum difference of 1% was observed when the relative error is kept below 0.1%. A GPU-based MC code was developed for dose calculations using detailed patient and CT scanner models. Efficiency and accuracy were both guaranteed in this code. Scalability of the code was confirmed on the dual-GPU system. © 2012 American Association of Physicists in Medicine.

  13. Effect of Accelerator in Green Synthesis of Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Kamyar Shameli

    2010-10-01

    Full Text Available Silver nanoparticles (Ag-NPs were successfully synthesized in the natural polymeric matrix. Silver nitrate, gelatin, glucose, and sodium hydroxide have been used as silver precursor, stabilizer, reducing agent, and accelerator reagent, respectively. This study investigated the role of NaOH as the accelerator. The resultant products have been confirmed to be Ag-NPs using powder X-ray diffraction (PXRD, UV-vis spectroscopy, and transmission electron microscopy (TEM. The colloidal sols of Ag-NPs obtained at different volumes of NaOH show strong and different surface plasmon resonance (SPR peaks, which can be explained from the TEM images of Ag-NPs and their particle size distribution. Compared with other synthetic methods, this work is green, rapid, and simple to use. The newly prepared Ag-NPs may have many potential applications in chemical and biological industries.

  14. Statistical methods for transverse beam position diagnostics with higher order modes in third harmonic 3.9 GHz superconducting accelerating cavities at FLASH

    CERN Document Server

    Zhang, P; Jones, R M

    2014-01-01

    Beam-excited higher order modes (HOM) can be used to provide beam diagnostics. Here we focus on 3.9 GHz superconducting accelerating cavities. In particular we study dipole mode excitation and its application to beam position determinations. In order to extract beam position information, linear regression can be used. Due to a large number of sampling points in the waveforms, statistical methods are used to effectively reduce the dimension of the system, such as singular value decomposition (SVD) and k-means clustering. These are compared with the direct linear regression (DLR) on the entire waveforms. A cross-validation technique is used to study the sample independent precisions of the position predictions given by these three methods. A RMS prediction error in the beam position of approximately 50 micron can be achieved by DLR and SVD, while k-means clustering suggests 70 micron.

  15. Method of rheological characterization of polymer materials by identification of the prony viscoelastic model according to data of static and dynamic accelerated tests

    Science.gov (United States)

    Shil'ko, S. V.; Gavrilenko, S. L.; Panin, S. V.; Alexenko, V. O.

    2017-12-01

    A method for determining rheological parameters of the Prony model describing the process of viscoelastic deformation of a material was developed based on the results of dynamic mechanical analysis. For the approbation of the method, static (uniaxial tension) and dynamic (three-point bending) mechanical tests of polymer composites were carried out. Based on the analytical dependence of the storage modulus on the parameters of the Prony model, the parameters of the shear function are determined. The results of the static and dynamic analysis are in good agreement. The proposed technique allows us to accelerate the determination of rheological parameters of polymer materials and recommend it to the calculation of the stress-strain state of structural elements and friction joints during their long operation at elevated temperature.

  16. Domain decomposition and CMFD acceleration applied to discrete-ordinate methods for the solution of the neutron transport equation in XYZ geometries

    International Nuclear Information System (INIS)

    Masiello, Emiliano; Martin, Brunella; Do, Jean-Michel

    2011-01-01

    A new development for the IDT solver is presented for large reactor core applications in XYZ geometries. The multigroup discrete-ordinate neutron transport equation is solved using a Domain-Decomposition (DD) method coupled with the Coarse-Mesh Finite Differences (CMFD). The later is used for accelerating the DD convergence rate. In particular, the external power iterations are preconditioned for stabilizing the oscillatory behavior of the DD iterative process. A set of critical 2-D and 3-D numerical tests on a single processor will be presented for the analysis of the performances of the method. The results show that the application of the CMFD to the DD can be a good candidate for large 3D full-core parallel applications. (author)

  17. Quantum synthetic aperture radar

    Science.gov (United States)

    Lanzagorta, Marco; Jitrik, Oliverio; Uhlmann, Jeffrey; Venegas-Andraca, Salvador E.

    2017-05-01

    Synthetic aperture radar (SAR) uses sensor motion to generate finer spatial resolution of a given target area. In this paper we explore the theoretical potential of quantum synthetic aperture quantum radar (QSAR). We provide theoretical analysis and simulation results which suggest that QSAR can provide improved detection performance over classical SAR in the high-noise low-brightness regime.

  18. Designing synthetic biology.

    Science.gov (United States)

    Agapakis, Christina M

    2014-03-21

    Synthetic biology is frequently defined as the application of engineering design principles to biology. Such principles are intended to streamline the practice of biological engineering, to shorten the time required to design, build, and test synthetic gene networks. This streamlining of iterative design cycles can facilitate the future construction of biological systems for a range of applications in the production of fuels, foods, materials, and medicines. The promise of these potential applications as well as the emphasis on design has prompted critical reflection on synthetic biology from design theorists and practicing designers from many fields, who can bring valuable perspectives to the discipline. While interdisciplinary connections between biologists and engineers have built synthetic biology via the science and the technology of biology, interdisciplinary collaboration with artists, designers, and social theorists can provide insight on the connections between technology and society. Such collaborations can open up new avenues and new principles for research and design, as well as shed new light on the challenging context-dependence-both biological and social-that face living technologies at many scales. This review is inspired by the session titled "Design and Synthetic Biology: Connecting People and Technology" at Synthetic Biology 6.0 and covers a range of literature on design practice in synthetic biology and beyond. Critical engagement with how design is used to shape the discipline opens up new possibilities for how we might design the future of synthetic biology.

  19. Implementation of TTIK method and time of flight for resonance reaction studies at heavy ion accelerator DC-60

    Energy Technology Data Exchange (ETDEWEB)

    Nurmukhanbetova, A.K. [National Laboratory Astana, Nazarbayev University, Astana 010000 (Kazakhstan); Goldberg, V.Z. [Cyclotron Institute, Texas A& M University, College Station, TX (United States); Nauruzbayev, D.K. [National Laboratory Astana, Nazarbayev University, Astana 010000 (Kazakhstan); Saint Petersburg State University, Saint Petersburg (Russian Federation); Rogachev, G.V. [Cyclotron Institute, Texas A& M University, College Station, TX (United States); Golovkov, M.S. [Joint Institute of Nuclear Research, Dubna (Russian Federation); Dubna State University, Dubna (Russian Federation); Mynbayev, N.A. [National Laboratory Astana, Nazarbayev University, Astana 010000 (Kazakhstan); Artemov, S.; Karakhodjaev, A. [Institute of Nuclear Physics, Tashkent (Uzbekistan); Kuterbekov, K. [L.N. Gumilov Eurasian National University, Astana (Kazakhstan); Rakhymzhanov, A. [National Laboratory Astana, Nazarbayev University, Astana 010000 (Kazakhstan); Berdibek, Zh. [School of Science and Technology, Nazarbayev University, Astana (Kazakhstan); Ivanov, I. [Institute of Nuclear Physics, Astana (Kazakhstan); Tikhonov, A. [School of Science and Technology, Nazarbayev University, Astana (Kazakhstan); Zherebchevsky, V.I.; Torilov, S. Yu. [Saint Petersburg State University, Saint Petersburg (Russian Federation); Tribble, R.E. [Cyclotron Institute, Texas A& M University, College Station, TX (United States)

    2017-03-01

    To study resonance reactions of heavy ions at low energy we have combined the Thick Target Inverse Kinematics Method (TTIK) with Time of Flight method (TF). We used extended target and TF to resolve the identification problems of various possible nuclear processes inherent to the simplest popular version of TTIK. Investigations of the {sup 15}N interaction with hydrogen and helium gas targets by using this new approach are presented.

  20. Superconducting Accelerator Magnets

    CERN Document Server

    Mess, K H; Wolff, S

    1996-01-01

    The main topic of the book are the superconducting dipole and quadrupole magnets needed in high-energy accelerators and storage rings for protons, antiprotons or heavy ions. The basic principles of low-temperature superconductivity are outlined with special emphasis on the effects which are relevant for accelerator magnets. Properties and fabrication methods of practical superconductors are described. Analytical methods for field calculation and multipole expansion are presented for coils without and with iron yoke. The effect of yoke saturation and geometric distortions on field quality is studied. Persistent magnetization currents in the superconductor and eddy currents the copper part of the cable are analyzed in detail and their influence on field quality and magnet performance is investigated. Superconductor stability, quench origins and propagation and magnet protection are addressed. Some important concepts of accelerator physics are introduced which are needed to appreciate the demanding requirements ...

  1. Accelerated treatment.

    Science.gov (United States)

    Barkley, H T

    1985-05-01

    In the first third of this century, the prevailing concept was that malignant cells had a brief period of sensitivity and radiation treatments were ideally given in overall times of 2 weeks or less. Following the Second World War, routine treatment times were extended to 5 to 8 weeks to avoid severe acute normal tissue reactions and achieve higher tumor doses. In reaction to these prolonged overall times, a series of large-fraction, shortened-overall-time clinical experiments were attempted, with disastrous normal tissue effects and poor tumor control. More recently, attempts to accelerate treatment have been accomplished by utilizing multiple fractions per day or semicontinuous irradiation. Unfortunately, the majority of these attempts have been forced by the occurrence of unacceptable normal tissue reactions to significantly reduce total dose or introduce lengthy splits in treatment. These results suggest that in our current state of knowledge accelerated schedules be reserved for use in the treatment of rapidly proliferating neoplasms or for palliation.

  2. Synergistic Synthetic Biology: Units in Concert

    Science.gov (United States)

    Trosset, Jean-Yves; Carbonell, Pablo

    2013-01-01

    Synthetic biology aims at translating the methods and strategies from engineering into biology in order to streamline the design and construction of biological devices through standardized parts. Modular synthetic biology devices are designed by means of an adequate elimination of cross-talk that makes circuits orthogonal and specific. To that end, synthetic constructs need to be adequately optimized through in silico modeling by choosing the right complement of genetic parts and by experimental tuning through directed evolution and craftsmanship. In this review, we consider an additional and complementary tool available to the synthetic biologist for innovative design and successful construction of desired circuit functionalities: biological synergies. Synergy is a prevalent emergent property in biological systems that arises from the concerted action of multiple factors producing an amplification or cancelation effect compared with individual actions alone. Synergies appear in domains as diverse as those involved in chemical and protein activity, polypharmacology, and metabolic pathway complementarity. In conventional synthetic biology designs, synergistic cross-talk between parts and modules is generally attenuated in order to verify their orthogonality. Synergistic interactions, however, can induce emergent behavior that might prove useful for synthetic biology applications, like in functional circuit design, multi-drug treatment, or in sensing and delivery devices. Synergistic design principles are therefore complementary to those coming from orthogonal design and may provide added value to synthetic biology applications. The appropriate modeling, characterization, and design of synergies between biological parts and units will allow the discovery of yet unforeseeable, novel synthetic biology applications. PMID:25022769

  3. Synergistic Synthetic Biology: Units in Concert

    International Nuclear Information System (INIS)

    Trosset, Jean-Yves; Carbonell, Pablo

    2013-01-01

    Synthetic biology aims at translating the methods and strategies from engineering into biology in order to streamline the design and construction of biological devices through standardized parts. Modular synthetic biology devices are designed by means of an adequate elimination of cross-talk that makes circuits orthogonal and specific. To that end, synthetic constructs need to be adequately optimized through in silico modeling by choosing the right complement of genetic parts and by experimental tuning through directed evolution and craftsmanship. In this review, we consider an additional and complementary tool available to the synthetic biologist for innovative design and successful construction of desired circuit functionalities: biological synergies. Synergy is a prevalent emergent property in biological systems that arises from the concerted action of multiple factors producing an amplification or cancelation effect compared with individual actions alone. Synergies appear in domains as diverse as those involved in chemical and protein activity, polypharmacology, and metabolic pathway complementarity. In conventional synthetic biology designs, synergistic cross-talk between parts and modules is generally attenuated in order to verify their orthogonality. Synergistic interactions, however, can induce emergent behavior that might prove useful for synthetic biology applications, like in functional circuit design, multi-drug treatment, or in sensing and delivery devices. Synergistic design principles are therefore complementary to those coming from orthogonal design and may provide added value to synthetic biology applications. The appropriate modeling, characterization, and design of synergies between biological parts and units will allow the discovery of yet unforeseeable, novel synthetic biology applications.

  4. An accurate Rb density measurement method for a plasma wakefield accelerator experiment using a novel Rb reservoir

    CERN Document Server

    Öz, E.; Muggli, P.

    2016-01-01

    A method to accurately measure the density of Rb vapor is described. We plan on using this method for the Advanced Wakefield (AWAKE)~\\cite{bib:awake} project at CERN , which will be the world's first proton driven plasma wakefield experiment. The method is similar to the hook~\\cite{bib:Hook} method and has been described in great detail in the work by W. Tendell Hill et. al.~\\cite{bib:densitymeter}. In this method a cosine fit is applied to the interferogram to obtain a relative accuracy on the order of $1\\%$ for the vapor density-length product. A single-mode, fiber-based, Mach-Zenhder interferometer will be built and used near the ends of the 10 meter-long AWAKE plasma source to be able to make accurate relative density measurement between these two locations. This can then be used to infer the vapor density gradient along the AWAKE plasma source and also change it to the value desired for the plasma wakefield experiment. Here we describe the plan in detail and show preliminary results obtained using a prot...

  5. Laser Accelerator

    Science.gov (United States)

    2014-09-01

    Photocathode emitters eject electrons from the cathode by the photoelectric effect. A drive laser source shines light energy onto a metal or...synchronized so that the electrons ejected via the photoelectric effect are properly accelerated. 15 Figure 2.4: Cross-section of a triple spoke cavity, from...2.3: Available Pulsed Magnets at PFF LANL. SP = Short Pulse. MP = Mid-Pulse, after [19] Cell No. Magnet Pulse Duration (ms) Bore (mm) 1 50 T SP 25 24

  6. Accelerating networks

    International Nuclear Information System (INIS)

    Smith, David M D; Onnela, Jukka-Pekka; Johnson, Neil F

    2007-01-01

    Evolving out-of-equilibrium networks have been under intense scrutiny recently. In many real-world settings the number of links added per new node is not constant but depends on the time at which the node is introduced in the system. This simple idea gives rise to the concept of accelerating networks, for which we review an existing definition and-after finding it somewhat constrictive-offer a new definition. The new definition provided here views network acceleration as a time dependent property of a given system as opposed to being a property of the specific algorithm applied to grow the network. The definition also covers both unweighted and weighted networks. As time-stamped network data becomes increasingly available, the proposed measures may be easily applied to such empirical datasets. As a simple case study we apply the concepts to study the evolution of three different instances of Wikipedia, namely, those in English, German, and Japanese, and find that the networks undergo different acceleration regimes in their evolution

  7. The Brookhaven National Laboratory Accelerator Test Facility

    International Nuclear Information System (INIS)

    Batchelor, K.

    1992-01-01

    The Brookhaven National Laboratory Accelerator Test Facility comprises a 50 MeV traveling wave electron linear accelerator utilizing a high gradient, photo-excited, raidofrequency electron gun as an injector and an experimental area for study of new acceleration methods or advanced radiation sources using free electron lasers. Early operation of the linear accelerator system including calculated and measured beam parameters are presented together with the experimental program for accelerator physics and free electron laser studies

  8. Workshop on acceleration of the validation and regulatory acceptance of alternative methods and implementation of testing strategies

    DEFF Research Database (Denmark)

    Piersma, A. H.; Burgdorf, T.; Louekari, K.

    2018-01-01

    This report describes the proceedings of the BfR-RIVM workshop on validation of alternative methods which was held 23 and 24 March 2017 in Berlin, Germany. Stakeholders from governmental agencies, regulatory authorities, universities, industry and the OECD were invited to discuss current problems......-focused hazard and risk assessment of chemicals requires an open mind towards stepping away from the animal study as the gold standard and defining human biologically based regulatory requirements for human hazard and risk assessment.......This report describes the proceedings of the BfR-RIVM workshop on validation of alternative methods which was held 23 and 24 March 2017 in Berlin, Germany. Stakeholders from governmental agencies, regulatory authorities, universities, industry and the OECD were invited to discuss current problems...... concerning the regulatory acceptance and implementation of alternative test methods and testing strategies, with the aim to develop feasible solutions. Classical validation of alternative methods usually involves one to one comparison with the gold standard animal study. This approach suffers from...

  9. A Simple but Powerful Heuristic Method for Accelerating k-Means Clustering of Large-Scale Data in Life Science.

    Science.gov (United States)

    Ichikawa, Kazuki; Morishita, Shinichi

    2014-01-01

    K-means clustering has been widely used to gain insight into biological systems from large-scale life science data. To quantify the similarities among biological data sets, Pearson correlation distance and standardized Euclidean distance are used most frequently; however, optimization methods have been largely unexplored. These two distance measurements are equivalent in the sense that they yield the same k-means clustering result for identical sets of k initial centroids. Thus, an efficient algorithm used for one is applicable to the other. Several optimization methods are available for the Euclidean distance and can be used for processing the standardized Euclidean distance; however, they are not customized for this context. We instead approached the problem by studying the properties of the Pearson correlation distance, and we invented a simple but powerful heuristic method for markedly pruning unnecessary computation while retaining the final solution. Tests using real biological data sets with 50-60K vectors of dimensions 10-2001 (~400 MB in size) demonstrated marked reduction in computation time for k = 10-500 in comparison with other state-of-the-art pruning methods such as Elkan's and Hamerly's algorithms. The BoostKCP software is available at http://mlab.cb.k.u-tokyo.ac.jp/~ichikawa/boostKCP/.

  10. Workshop on acceleration of the validation and regulatory acceptance of alternative methods and implementation of testing strategies.

    NARCIS (Netherlands)

    Piersma, A H; Burgdorf, T; Louekari, K; Desprez, B; Taalman, R; Landsiedel, R; Barroso, J; Rogiers, V; Eskes, C; Oelgeschläger, M; Whelan, M; Braeuning, A; Vinggaard, A M; Kienhuis, A; van Benthem, J; Ezendam, J

    2018-01-01

    This report describes the proceedings of the BfR-RIVM workshop on validation of alternative methods which was held 23 and 24 March 2017 in Berlin, Germany. Stakeholders from governmental agencies, regulatory authorities, universities, industry and the OECD were invited to discuss current problems

  11. Acceleration of the nodal program FERM

    International Nuclear Information System (INIS)

    Nakata, H.

    1985-01-01

    Acceleration of the nodal FERM was tried by three acceleration schemes. Results of the calculations showed the best acceleration with the Tchebyshev method where the savings in the computing time were of the order of 50%. Acceleration with the Assymptotic Source Extrapoltation Method and with the Coarse-Mesh Rebalancing Method did not result in any improvement on the global computational time, although a reduction in the number of outer iterations was observed. (Author) [pt

  12. Acceleration of the FERM nodal program

    International Nuclear Information System (INIS)

    Nakata, H.

    1985-01-01

    It was tested three acceleration methods trying to reduce the number of outer iterations in the FERM nodal program. The results obtained indicated that the Chebychev polynomial acceleration method with variable degree results in a economy of 50% in the computer time. Otherwise, the acceleration method by source asymptotic extrapolation or by zonal rebalance did not result in economy of the global computer time, however some acceleration had been verified in outer iterations. (M.C.K.) [pt

  13. Synthetic biological networks

    International Nuclear Information System (INIS)

    Archer, Eric; Süel, Gürol M

    2013-01-01

    Despite their obvious relationship and overlap, the field of physics is blessed with many insightful laws, while such laws are sadly absent in biology. Here we aim to discuss how the rise of a more recent field known as synthetic biology may allow us to more directly test hypotheses regarding the possible design principles of natural biological networks and systems. In particular, this review focuses on synthetic gene regulatory networks engineered to perform specific functions or exhibit particular dynamic behaviors. Advances in synthetic biology may set the stage to uncover the relationship of potential biological principles to those developed in physics. (review article)

  14. Synthetic Base Fluids

    Science.gov (United States)

    Brown, M.; Fotheringham, J. D.; Hoyes, T. J.; Mortier, R. M.; Orszulik, S. T.; Randles, S. J.; Stroud, P. M.

    The chemical nature and technology of the main synthetic lubricant base fluids is described, covering polyalphaolefins, alkylated aromatics, gas-to-liquid (GTL) base fluids, polybutenes, aliphatic diesters, polyolesters, polyalkylene glycols or PAGs and phosphate esters.Other synthetic lubricant base oils such as the silicones, borate esters, perfluoroethers and polyphenylene ethers are considered to have restricted applications due to either high cost or performance limitations and are not considered here.Each of the main synthetic base fluids is described for their chemical and physical properties, manufacture and production, their chemistry, key properties, applications and their implications when used in the environment.

  15. 2014 Joint International Accelerator School: Beam Loss and Accelerator Protection

    CERN Document Server

    JAS - Joint US-CERN-Japan-Russia Accelerator School

    2016-01-01

    Many particle accelerators operate with very high beam power and very high energy stored in particle beams as well as in magnet systems. In the future, the beam power in high intensity accelerators will further increase. The protection of the accelerator equipment from the consequences of uncontrolled release of the energy is essential. This was the motivation for organizing a first school on beam losses and accelerator protection (in general referred to as machine protection). During the school the methods and technologies to identify, mitigate, monitor and manage the technical risks associated with the operation of accelerators with high-power beams or subsystems with large stored energy were presented. At the completion of the school the participants should have been able to understand the physical phenomena that can damage machine subsystems or interrupt operations and to analyze an accelerator facility to produce a register of technical risks and the corresponding risk mitigation and management strategie...

  16. Accelerated parabolic Radon domain 2D adaptive multiple subtraction with fast iterative shrinkage thresholding algorithm and its application in parabolic Radon domain hybrid demultiple method

    Science.gov (United States)

    Li, Zhong-xiao; Li, Zhen-chun

    2017-08-01

    efficiency while maintaining its accuracy. Synthetic and field data examples demonstrate the effectiveness of the proposed FISTA based parabolic Radon domain 2D adaptive multiple subtraction and its application in the parabolic Radon domain hybrid demultiple method.

  17. Advanced concepts for acceleration

    International Nuclear Information System (INIS)

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations

  18. Bulk Analysis Method of Gold Determination in Ores Using Epithermal Neutrons of Electron Accelerator Microtron MT-22

    CERN Document Server

    Gerbish, Sh; Baatarkhuu, D; Ganbold, G; Belov, A G

    2004-01-01

    Bulk analysis method of gold determination in ores by Instrumental Neutron Activation Analysis (INAA) is described. The powder (100-200 mesh) samples were irradiated in Cd foils of 1 mm thick with photo-neutrons at the Microtron MT-22 of the Nuclear Research Center, Mongolian State University (Ulaanbaatar). The sensitivity of 0.1 mg/kg Au can be obtained using 30-50 g samples and irradiation time of 1-2 h.

  19. Adapting capillary gel electrophoresis as a sensitive, high-throughput method to accelerate characterization of nucleic acid metabolic enzymes

    OpenAIRE

    Greenough, Lucia; Schermerhorn, Kelly M.; Mazzola, Laurie; Bybee, Joanna; Rivizzigno, Danielle; Cantin, Elizabeth; Slatko, Barton E.; Gardner, Andrew F.

    2015-01-01

    Detailed biochemical characterization of nucleic acid enzymes is fundamental to understanding nucleic acid metabolism, genome replication and repair. We report the development of a rapid, high-throughput fluorescence capillary gel electrophoresis method as an alternative to traditional polyacrylamide gel electrophoresis to characterize nucleic acid metabolic enzymes. The principles of assay design described here can be applied to nearly any enzyme system that acts on a fluorescently labeled o...

  20. A Fourier-based compressed sensing technique for accelerated CT image reconstruction using first-order methods.

    Science.gov (United States)

    Choi, Kihwan; Li, Ruijiang; Nam, Haewon; Xing, Lei

    2014-06-21

    As a solution to iterative CT image reconstruction, first-order methods are prominent for the large-scale capability and the fast convergence rate [Formula: see text]. In practice, the CT system matrix with a large condition number may lead to slow convergence speed despite the theoretically promising upper bound. The aim of this study is to develop a Fourier-based scaling technique to enhance the convergence speed of first-order methods applied to CT image reconstruction. Instead of working in the projection domain, we transform the projection data and construct a data fidelity model in Fourier space. Inspired by the filtered backprojection formalism, the data are appropriately weighted in Fourier space. We formulate an optimization problem based on weighted least-squares in the Fourier space and total-variation (TV) regularization in image space for parallel-beam, fan-beam and cone-beam CT geometry. To achieve the maximum computational speed, the optimization problem is solved using a fast iterative shrinkage-thresholding algorithm with backtracking line search and GPU implementation of projection/backprojection. The performance of the proposed algorithm is demonstrated through a series of digital simulation and experimental phantom studies. The results are compared with the existing TV regularized techniques based on statistics-based weighted least-squares as well as basic algebraic reconstruction technique. The proposed Fourier-based compressed sensing (CS) method significantly improves both the image quality and the convergence rate compared to the existing CS techniques.